when it ask what program to open with what do i us when downloading mpc,i downloaded it and cant find it

well... You specify the path to save it to, so only you know that. You could just search for it (doesn't Windows2000 have some kind of search?)

Incase you don't have an unzipping tool you could try this one (says it's freeware and supports Windows2000) http://www.dirfile.com/ace_zip.htm