CPU Usage 100%

[Sakumo]

Well, you are using a single core.

Are you scanning and running Firefox at the same time?

[Ronin]

Are you running the latest version of FF?
Are you running the lastest version of the flash?
Are you running the lastest version of java?
Are your video drivers up to date?
Are your Audio drivers up to date?
Have you cleared cookies and cache?
Do you use add-ons and which?

What is "multible" things?
Comparable to 5, 10 or 20 youtube pages?

[Halaster]

He may want to run Windows using less services and not run so many things at once.

http://www.blackviper.com/Windows_7/servicecfg.htm

[Halaster]

I would not even get infected by Internet malware in the first place. That's what you get for not setting up your Windows Hosts file.

http://www.mvps.org/winhelp2002/hosts.htm

http://en.wikipedia.org/wiki/Hosts_file

You can set up your Hosts file easily with HostsMan.

If you're going to use Internet Explorer, it doesn't hurt to immunize it with Spywareblaster.

http://www.javacoolsoftware.com/spywareblaster.html