Pacian, I need to ask - did you run Rootkit Revealer even before I asked? Because there are 4 traces of separate runs in your first hijackthis log.... then, after I got you to delete them [post #16 above] there are now in your last hijackthis log 3 new runs of that service showing?!! Did you actually run Rootkit Revealer 3 times since you posted the previous hijackthis log?

I didn't run Rootkit Revealer that many times but I did run C Cleaner that many times.

Okay, CCleaner would not be the culprit.. your sys shows a total of seven RR runs that I have seen. Somewhere I remember seeing a reference to an AIM virus or trojan that strangely included a copy of sysinternals rootkit revealer... I am wondering if it runs RR when you try to start the infected AIM pgm.
Naturally I cannot at the moment find that reference.... sigh...

You might try running this:
http://www.jayloden.com/aimfix.htm

I actually tried starting AIM on another user on the computer and it worked. It seems it's only limited to my account.

AIMFIX didn't work.

I'm sorry, but I don't think I can help you any further, pacian... it looks like a registry setting is blocking your account from using AIM, but I would have thought a reinstallation would have cleared that. There is obviously a setting outside of AIM that affects you; I have no ideas on that. It would have been nice if you could have managed a Panda scan as per below, but I don't think that would solve your current problem, anyway.
==Please use IE to do an online scan at panda:- http://www.pandasoftware.com/products/activescan?
-select a link to the scan... free online virus scan...., enter a valid? email and follow through, choosing My Computer for a full system scan.
Post the log it produces here...
Cheers. I hope someonelse knows what could be the block.

Thanks for all your help. I'll try that panda scan.