So you're saying they stay home all the time jacking off or playing video games? Would you classify them as losers?
I usually wouldn't say to dump your friends b/c they are considered 'losers' (who cares, anyways?), but if they're holding you back, it might be time to move on.
Give them a warning, tell 'em that they are being jackasses. Invite them to come out with you, to learn how to have fun. The primary purpose of friends is to be people you can have fun with.
If you really like these guys, and are cool when you're just hanging out at home, then you should probably do what Splat suggested. Find some more outgoing friends; you always need a wingman or two.
Beware though that your current friends may get pissed if you start hanging out with your new friends a lot; if you don't manage things correctly you might lose them. Just a heads-up.
Bottom-line: Don't let your friends hold you back. Find people you can have a blast with, and people you can learn from.
Good luck,- -E-Z