teresarae,

have you tried doing an online virus/malware/trojan scan? it couldn't hurt to try, especially if your antivirus installed on your machine has become compromised in some way.
Trendmicro has a good, thorough and free online scanner, it's at http://housecall.trendmicro.com . You should probably turn off System Restore before doing the scan, otherwise possible infections could be lurking there and re-manifest themselves even if the online scanner cleans them out.

HTH!