I have the same thing going on my comp. Although my task manager runs fine. But i think you have a virus, just like we had.
Try installing an antivirusprogram other than norton (we did macafee) that will probably show you you have a virus.
try to get it of and i hope you have back ups of your computer.
If you don't have those, don't trow anything of your comp because that can/will do serious harm.
Or just let somebody who knows a lot about computers take a look at yours, i don't say it will help, but he won't destroy important files