Barbara pre-16
Not Batgirl, A young, athletic nerd and wallflower. No romantic relationships - and very seldom played. At age 8 she was adopted by Jim Gordon after her alcoholic father managed to kill her mother in a car crash and then drank himself into a bottle. (She's actually the biological daughter of Roger Gordon- Jim Gordon's brother, and is named after the Barbara Gordon that is Jim Gordon's wife). James Gordon Jr. as a creation of the DCNu hasn't been worked into her timeline (although could be if someone wanted to play him). If she refers to Roger Gordon at all it's as a sperm donor.
Barbara aged 16 - "Baby Batgirl"
At 16, wanting to annoy her father, Barbara made herself and put on a female Batman halloween costume - although it was based at least as much on Catwoman's costume as Batman's. The party got crashed as soon as she arrived by a few supervillains, and as she was wearing a Batman themed costume she decided to try and drive them off and, almost miraculously succeeded. (Who the supervillains were doesn't matter - and sources differ).
At school she's not as dedicated as she pretends to be - but simultaneously manages a straight A average and is trying to make the national team at gymnastics, and potentialy qualify for the Olympics (or the "Summer Games" for Young Justice fans), encouraged by her father. She never quite does - and probably wouldn't have made it past sixth spot on the team, although it might have been enough for a team medal.
Her love life - she was getting no dates at school, in part because she was a wallflower and in part because half the boys had Batgirl pictures on their walls and she just couldn't take that seriously. She had two crushes - one on Killer Moth (her first personal supervillain), and one on Poison Ivy (which she put down to the pheromones). And a lot of her wanted to be Catwoman, although she knew she'd break her dad's heart if she turned criminal.
She's very happy-go-lucky at this age, pretty inexperienced, and generally finds being Batgirl an absolute blast rather than any sort of matter of principle. But taking lives as opposed to saving them would be crossing a line she won't.
(Note: I defaut to Batgirl Year 1 for this period - but refuse to take any graphic novel with a female protagonist that takes more than 100 pages to pass the Bedchel Test as exclusive canon so there's a fair bit of DCAU graphic novel in there even though I can't remember it so well).
Barbara aged 18 - The start of college, and out of the closet
Barbara went to college a year early and had Katarina Armstrong, junior superspy, as her college roommate. The first person she knew who was both her own age and could keep up with her (and later demonstrated that winning silly athletic competitions was more important than friendship, making a deliberate professional foul on Barbara). The relationship (not Barbara's first, but pretty close) was more than platonic. Chuck Dixon, one of her writers, claims she's straight - and then wrote this scene between two "straight" women - as well as writing Batgirl: Year One above.
As Batgirl she's more or less a continuation of the above - although a whole lot better at fighting and with a few more issues drom aftereffects of combat. Oh, and she's a serious adrenaline junkie. Most of Gotham's thugs are actually semi-protective of her, and there's almost chivalry both ways. If Batman's coming in by the front door he's coming in breaking bones - and Batgirl will be by the back door allowing the thugs to put up token resistance before she handcuffs them (and most don't mind being cuffed by a pretty girl, especially when the alternative is Batman coming in breaking bones) - and when she gets captured it's often deliberate and there's a rough chivalry protecting her. Her costume has changed - it's not just bullet and knife resistant these days, but she's actually wearing two wigs; a synthetic red wig over a brunette wig of real human hair.
She has definite body image issues - on the one hand she's a pinup, on the other it's not her that people keep asking out and proposing marriage to. And Batgirl pulls a Batman-style disappearance before answering.
Barbara aged 22 - Batgirl was a Librarian
Barbara graduated college fast and with a very strong degree in Information Science. Her day job is part time municipal librarian - but that's mostly a hobby - her income comes from being a research librarian on retainer to Waynecorp, Kord Industries, and a few other people (and she didn't pull Bat-strings to get there).
As Batgirl she's on top of her game and utterly unafraid of anything. This is a problem - too many run ins with Scarecrow have effectively burned out her ability to feel fear. She's aware it's a problem. But she's also utterly unafraid of anything because she's brought everything up to and including renegade Kryptonians down herself. Part of it she's earned. Her eidetic memory is also extremely useful but starting to turn into a liability because if she can't forget she has a lot of experiences in there.
She's single (the fling with Nightwing really didn't work out) but has no problem with that; it's more that she doesn't have room in her life for a significant other than anything else.
Barbara aged 25 - Congresswoman Gordon
The description of Barbara as Congresswoman Gordon is a bit of an in joke. She isn't actually a member of Congress right at the minimum age available. Instead she's a member of staff of one of the congressmen from NY State, officially just graduated from Intern. But what she is is a fixer. She controls the vote of her Congressman - and a dozen others. She can write briefing papers for bipartisan support and knows who will be swayed by what not-bribes. There are a number of staffers who have far more influence than any actual congresscritter and Barbara is one of them.
As Batgirl she's mostly retired - too many after effects of Gothamite villains, and she's not as fast as she used to be. Gotham is in some ways rougher (there's actually less crime, but the crime is harsher) and the 'Batgirl walks into a trap to find plans' techniques no longer work. Her fear response is recovering and she's aware of how much damage there has been, so only puts on the costume in an emergency.
Barbara aged 26 - The Killing Joke
Barbara gets shot and crippled from the waist down by the Joker - and spirals into depression. PSLs with Barbara at 26 are by invitation only.
Barbara aged 28 - the Rise of Oracle
Barbara's been confined to a wheelchair for the past three years, and her mentor, Amanda Waller, has just put herself in jail for a crime she did commit. After teaching Barbara how to run an ops team (including how to pick up as control when The Wall got injured). She's confined to a wheelchair and bitter about it (and her body image issues have returned thanks to that). Oracle is about as prickly as a porcupine.
As a hacker she's overrated and knows it. There are plenty better out there, but when you have access to multiple forms of alien technology brute force hacks suddenly become a whole lot easier. She's also got much more personal knowledge of the entire superhero and supervillain community than literally any other hacker out there so although her raw technical skill is merely very good her ability to get through systems is one of the best on the planet.
Barbara aged 31 - the Birds' Nest
Circa Birds of Prey 75 (i.e. the middle of Gail Simone's run). Barbara is coming to terms with her issues although is still prickly, snappy, defensive, and a schemer. But can see that she is where she is meant to be and the world wouldn't be the same without her. Coordinator of superteams (including her own) and the intel hub of the superhero community.
It's not all happy, of course, Amanda Waller has turned heel with a vengeance. Batman's past the point he should have retired, and getting more closed in on himself. And then there's the fallout from the mess that was Identity Crisis and Batman being mindcontrolled by Zatanna Zatara (who was stupid enough to make the vote binding earlier, meaning she herself had no choice there). But mostly Barbara herself is where she should be, if not where she planned to be. And is refusing medical treatment officially until it's mundane treatment but in practice because she knows that the temptation to return to her old identity as Batgirl would be overwhelming and would be stupid.
And to me her canon comes to a close with Gail Simone leaving the title at Birds of Prey #112. She doesn't grow in canon after that (indeed shrinking in the hands of inexpert writers) and the New 52 basically erases her history from 1988 to 2010. (Yes, I know about The Death of Oracle).