Finish school, maybe go to uni for computer science, land a decent job (i.e. something that pays well enough to allow me to enjoy living and involves writing code) and basically enjoy myself.

Very possible.
Not through solving all your problems but through autogenic training and brain restructering.
http://en.wikipedia.org/wiki/Autogenic_training
You will need to change the way your brain reacts to certain situations. You will need to do a lot of practice to be able to do that.

My goal is to have a decent life. Nothing fancy, I have no desire to work hard. Or a lot for that matter.
Will probably end up living with one of my friends together.
I don't see a point in marrying someone. That only means stress and limitation of my personal liberty. When someone loves me and I love that someone we will just stay close but not too close.
I don't want children. Even though I'm pretty good with them I see no point in having some.

To become a TSA

I have a couple goals...

Get smod someday (maybe GM back)
Finish my BS in Business Education in under three more years
Get a Store Management job before I graduate
Get a high figure job so my wife can stop working full time and go back to school
Write my grandfather a goodbye letter before its... too late
Help my sister through college
Get $20,000 CD for my son
Play my euphonium more often
Start composing music again
And more... may add later.

Go to uni, get a high paying job. Once got enough money, travel the world.

I want to be an Oceanographer. Only goal in life.

My overall goal is to become a world Shotokan Karate champion.

Become an animator, get a youtube partnership.

I have no idea of what I want to work with, but all I need is anything that gives me enough money for a stable life and that could be reasonably enjoyable.
That and, well, having a family and keeping in touch with my friends.

But that, in a very distant future, eh. I'm just 15.
For now all I have to do is keep studying so I can get to a good university, and enjoy life with my friends...

1.) Invent something epic/badass
2.) Be in a movie
3.) Respect everyone even if I hate them with a burning passion.
4.) Get straight A+ (Right now i'm only at A's )
5.) High five Will Ferrell
6.) Be in an episode of Charlie the Unicorn.
7.) Publish my joke book
8.) Be Known in the community.