windows XP

hello all ..
i had something going carzy in my computer i think it’s a virus but i just want to know if i can repair it or not ..
i hadsomething wrong with Run command if i press on run i had a nessage tells me that you cannot run this application and i found that my folder options also missed and i can’t run Regedit to show Folder opions…so how can i make it workable ….