Yahoo spyware

If, like me, you made the mistake of installing Yahoo Messenger version 7.5, and suddenly discovered that it made Yahoo your default search engine, there's a way of fixing it, but it's not easy. You can find the solution at the Simple Thoughts blog, but their solution didn't do the whole job for me. Nick Jones figured out the rest of it, and I added his solution to the "comments" section, so read all the way down.