Thought I would pass this on.
For weeks, I have been trying to find out why windows would freeze up when I either moved my mouse quickly or jumped from one search to another. I use Yahoo as my search engine. While I was doing this, I had to put up with the Yahoo toolbar hi-jacking my searches. I was thinking about getting rid of Yahoo altogether and use a different search engine when I decided to disable the Yahoo toolbar and see what happens. "BINGO".
Now no more freezing and my searches are no longer hijacked.
There were times when I had to download their toolbar after losing it and I may have picked the wrong site to download it from. Well for the time being, I will do without the toolbar and investigate this further.
So if you having a similar problem, try disabling the add-on toolbars; one at a time, starting with the last one added.