Virus Help!

[Breakyorself]

Okay, so recently I've been reinstalling a lot of stuff after my computer reset and it seems I've gotten a really, really, really, really, really, horrible virus.

It doesn't do much other than play annoying ads in the background which if I mute just restarts a minute later.

But it somehow found it's way into the legitimate windows/system32/svchost.exe

I know this, because Avast says so and it's able to play these annoying ads before the computer is logged on/is still booting up. Avast isn't able to do anything except warn me of it considering it's in the real svchost.

Is there any possible way of fixing this considering it's in such a crucial file that I can't just end or delete it?

[DavidR]

This needs further analysis by a malware removal specialist:
Go to this topic http://forum.avast.com/index.php?topic=53253.0 for information on Logs to assist in cleaning malware. Use the information about getting and using the tools and attach the logs here, not in the LOGS topic.

There may be some delay due to differing time zones and availability of the volunteer malware removal specialists.