IE7 slowed down randomly yesterday

[JesseM]

When loading a webpage, opening a new tab (to my homepage), or stopping in the middle of loading a page or clicking any buttons, IE7 freezes for about 4-10 seconds (just enough to really get on my nerves). This started for no apparent reason yesterday. Firefox works fine. When IE7 is loading a page, my CPU usage goes way up to around 50% until the page is loaded completely (and IE7 is unfrozen). I have tried disabling the phishing filter without luck.

Any ideas? Thanks.