IE 7 freezes up (not responding) and shoots CPU usage to 100%?

Over the last few months I’ve had to completely reinstall Windows XP Pro SP2 on my laptop. I reinstalled IE 7 on it recently after reinstalling Win XP for the upteenth time. Now I’m having issues when I use it. I’ll be browsing a site and IE freezes and CPU usage shoots up to 100% and won’t start working again so I have to repeatedly click the End Now button when it says the program stopped responding. I’m running Windows XP Pro SP3, but the problem started before I installed SP3. I’m at a loss as to why this is happening and what to do. Any help would be appreciated. Thanks!