thanks for the advice; i'll try what you guys are describing. Also, while i was submitting my original question, i had gone onto the geeksquad website and had run their free symantic "virus detection". it came back w/the following:
"74515 files scanned, 1 file(s) infected on your disk drives."
"No viruses were detected in memory."
"Your computer is infected with at least one known virus or Trojan horse."
"Search for the name of the threat(s) listed below on the Symantec Security Response site for removal information."
"C:\Documents and Settings\Administrator\Local Settings\Temp\_avast4_\unp120633472.tmp is infected with W32.Stration.AC@mm"
Any extra advice?