lots of those little windows that pop up where you have to answer yes or no are usually the culprits.. clicking yes or no doesn't matter.. either one will perform the same function.
I had a dialer icon put on my desktop, plus it added its number to my dialup connections list.
I just ctrl-alt-del anymore when they pop up.
I've got a program called
Reg Cleaner that I also use to get stuff out of the registry too.. it's pretty good.