svchost ,is a generic process name use by different programs ,I have 4 or 5 in mine .

http://www.liutilities.com/products/...brary/svchost/
and here is more info .
http://support.microsoft.com/?kbid=314056

It's normal.

There is a virus that executes as svchost.exe, but it likes to use 100% of the CPU when it can. I came across that when I forgot to put up the firewall. (Format and reinstall, then I want to make sure the internet's working, so I plug in the network cable...don't think of the firewall...oops.)

The virus is usuall disguised as ,but usually spelt different like SVXCHOST.EXE ,SXOCHOST.EXE or the like

I once saw a virus that spells scvhost.exe, I almost didn't notice it except that the anti-virus im running alerted me about it.

multiple instances of svchost.exe running at the same time is perfectly normal, except if you are infected with the blaster worm that executes it and takes up 100% of your cpu. What you need to do is keep your windows up to date with all the fixes and patches.