I had some problems using IE so I change to Firefox and Everything is nice and pretty for me.

I note the OP computer is only using a single processor maybe better to use dual core (or more) instead ?

Ok so you use Firefox,have you got the chat channel enabled on chess.com

if so disable chat and try again,it caused me loads of trouble when they introduced it.

Other wise do what I do,I use Google Chrome for this And firefox for everything else.No problems at all having both installed.