Computer Issues

damn computer. i can do everything i need to do on it...except run live update on anything. and no one seems to know how to fix my issues. this all started a while back when i couldn't run live update on norton antivirus. so the symantec support peeps advised me to uninstall the program and reinstall it...which didn't work. so they told me there was probably a leftover registry key, and i had to delete it. but the stupid registry editor won't open. my mouse arrow turns to an hourglass for a second, and then nothing happens. so, i was advised to restart with no programs running on startup...but MS configuration won't open, either. nothing else is messed up. everything else works fine. i suspect that when trendmicro removed a virus from my computer, some little file was deleted that controls these things. but no one can tell me what it is or how i can replace it. norton antivirus is the only file that won't install on my comp. all other installation cd's work fine. i even reinstalled windows, but my problem is still there. certain windows won't open...or they appear for, like, half a second and then disappear. so, i downloaded a trial version of trendmicro's pc-cillin, and it worked fine for a while. but now, i'm having the same problem with it and spyware doctor. but my anti-adware has been working fine through all these issues. so far, symantec support, microsoft support, and hp support have all been unable to solve my computer problems. the last resort: reinstall windows. done. and it didn't work. when i try to reinstall norton, the cursor flashes for a second or two and then nothing. i'm going to scream. i guess my next step is to go to DISL and harass tommy (our resident comupter guy). maybe he can help me. but i don't know.