User Accounts

My PC started locking up due to 100%CPU usage so I did
a repair with the Win XP CD and created another account.
When I log on using the new account everything seems to
be ok.
Simple things such as opening Outlook and clicking on
Help and Support in Win Eeplorer cause it to hang with
100%CPU usage.
I've spent the last 6 days trying to get an answer
without any success. It's always a different process that
hangs the PC. I've run virus checkers,restore point etc.
I'm ready to give up,there doesn't seem to be an answer!
If I delete that user will it delete all the items that
tree out under that user in Windows Explorer? All the
files and programs that appear when you click the + sign
are either listed on the new account or the All Users
account. I would like to get rid of all things associated
with that account since it has been a nightmare.