Have you tried cleaning out your Temporary Internet Files and Cookies?
IE 6.0 on XP Pro WON'T LOAD UNLESS I PRESS F5
thread608-809805
You could try disabling add-ons and or resetting Internet Explorer settings. (Help and Support article)
"If disabling add-ons doesn't solve the problem, try resetting Internet Explorer back to its default settings. This removes all changes that have been made to Internet Explorer since it was installed, but it does not delete your favorites or feeds.
Close all Internet Explorer or Windows Explorer windows.
Click to open Internet Explorer.
Click the Tools button, and then click Internet Options.
Click the Advanced tab, and then click Reset.
Click Reset.
When you are done, click Close, and then click OK.
Close Internet Explorer and reopen it for the changes to take effect."