Virus

Hello,
hi when i open up my computer after a log in the very first thing that pops up is a program called Privacy Cleaner again its not Pc Privacy cleaner its just (Privacy Cleaner ) it immediately starts cleaning i cant do anything else i cant even x out from this program so i have tried closing it with windows task manger but when i close it i cant c any of my icons not even the start botten not just a blank welcom come screen i have tried everthing i even tried opening my computer with safe mode the same thing happens i cant run any programs. btw i'm running on xp. could some one please help me its very annoying