Stupid W32/Blaster.worm virus wont let me use my comp. HELP!!!?

i think its trojan viruses and some other viruses but idk what to do cuz everytime i try to use a program it stop it before it opens and sais that its infected and cant open (security pop up/window). I tried to download some software security that i had but when i try to scan it closes out. I dont have any other typer of comp to use a flash drive to tranfer from there and i have items on this comp that i need and programs that i need so i cant reboot it. WHAT DO I DO???