cnetxp, That problem is probably the result of a virus or malware. Update your virus definitions and run a full scan. Also if you have any anti-spyware programs update them and run scans. Check out the link below.
My XP got CPU usage high close to 100% after I started to use dial-up internet, so I openned taskmsg.exe trying to delete that process. Unfortunately, that process is one of svchost.exe, which can't be killed. PC was running unbelievably slowly and it seems there are some programs running behind scene. When I tried to bring taskmsg.exe up again, the taskmsg.exe was hung, so I restarted the machine. After the system was back on again(of course it took very long to get restarted), I tried to bring taskmsg.exe again, this time, taskmsg.exe didn't hang but instead it flashed and dispeared. I can't see that taskmsg window at all except that flash moment, it happend the same thing when I tried to bring regedit from run. It just flashed and disapear, however, other programs run ok.
Thanks for help in advance.