[aliensexx]

Hii, I'm new here and I'm not sure if I posted in the right section, so sorry if it's not.

So here it goes, I'm playing Fly For Fun for a couple of years and you could make your own private server so I tried, my friend sent me some files that I require to make one so I downloaded it and my computer started to act strange so I restarted.
But then there's something wrong, it restarts itself again and again like for 3-4 times
and on the last try there's this screen with SelfRepair so I just let it be. Then when finally everything starts to work normal I've noticed my computer threw all the files away that caused the troubles so I of course, didn't re download it.
But when I start to download other things, I've noticed my downloading speed became so much slower.
It downloaded a file of 90 mb in 9 minutes while a file of 800-900 mb took me 8 minutes, so I was pretty shocked but I didn't do something about it.
So today I was searching on how to fix it and I found this person with the same problem and there was this guy and said you had to download RegistryBot so I did and after I downloaded it my (free) AVG says I downloaded 2 Trojans so I didn't know what to do so I removed the RegistryBot with CCleaner and that's it.
But now my computer really starts to hang, freeze, work slower...even my messenger gave up on me with errors.

Also the files came from my friend who sent it to me via Messenger conversation, he didn't have any troubles with it though.

I have an Acer Aspire Desktop M3641 Vista Home Premium Service Pack 1
Intell (R) Core (TM) 2 Quaad CPU Q 6600 4 Gb Ram 600 Gb Hard drive .

My desktop is only for 6 months old and this are my first issues with it.
So is there anything I can do without formatting it and do I have still this virus?

P.S: I don't have a lot of knowledge about programs,computers, ..etc so I might ask a lot of stupid questions.

Thanks,