Windows XP Cannot start or run anything

Hello,

I cannot open anything, when I try it says windows cannot open this file: and it mentions the file.. I got fed up and went to reinstall XP and it cant even read the disk that windows is on. When I double click setup after going to computer; d:; and browse it says that it cannot read setup. I tried the xp_exe_fix.reg but it cannot read that.. HELP, please!!