Well i was looking for some anti spyware/anti viruse software and a guy suggested avast and i knew was familiar so i downloaded it and then it rebooted my computer and a blue page popped up and it gave me an option to:
1:delete
2:delete all
3:repair
4:repair all
5:ignore
6:ignore all

So i picked "delete all" and it went down the line and said blah this is infected *deleteing* until it got to like 75% then it popped something ells up but i don't remmember what but i hit "delete all" again and when it finished it restarted like it usually does but when it gets to the desktop part nothing loads up.

Then i had a feeling it was most likely that 75% part.. :l
and btw my comp usually has that restore option when you start it up but when i hit "F10" it looks fine at first then it go's to a solid blue page with something that say's this "STOP: c000021a {Fatal System Error The Windows Logon Process system process terminated unexpectedly with a status of 0x0000005 (0x00000000 0x00000000) The system has been shut down".
so what should i do??

Sorry for the punctuation errors but im worried. >.<

I suggest that you start a new topic in the Malware Removal - HiJackThis™ Logs Go Here area.

Before you post a log click on this link --> You Must Read This Before Posting A Hijackthis Log
this will give you a few preparations to make, as well as instruction for posting your Hijackthis log.

If you are still having problems after being given a clean bill of health from the malware expert, then please return to THIS thread and we will pursue other options to help you solve your current problem(s).