Windows warnings after running CCleaner

I ran CCleaner for the first time last night after several other people I know said it is good. After I ran it my anti-virus program popped off and I started getting Windows warnings saying something to the point of....several vital Windows programs have been changed and will not work. You need to install Windows boot disk to fix the errors !.... well, that kinda got me nervous.

I am running Windows XP sp3

newest version of FF3

newest version of CCleaner

CA Security Suite from our DSL provider

Is there a chance I got an infected download ? Or am I missing something ?

If you downloaded CCleaner from http://www.ccleaner.com/ or http://www.filehippo.com/download_ccleaner/ those are trusted sources for downloading it.

Yep...got it from filehippo. I tried to system restore in Windows and it won't......still workin on it :(

You could always follow the guide here to make sure you have no malware

http://forum.piriform.com/index.php?showtopic=20120