services.msc won't run, an svchost.exe causing extreme lag

My computer(windows xp) has been having some problems lately. About 10 minutes after my computer is booted, an svchost.exe goes crazy and makes my computer lag BADLY. I always just close that svchost.exe and then my computer goes back to normal. Then about 5 minutes after that, my volume won't work. I clearly have audio devices installed but a window pops up telling me that I do not. So I've googled this problem and have been told to run services.msc. I go to "run" and type that in, press enter and nothing happens. My computer has just been epicfail lately and its very frustrating. All help greatly appreciated.