Like everything else to do with computers, you just have to learn to deal with it.
The major anti-spyware programs have already been mentioned. I have also occasionally found it necessary to clean up my Registry after deleting some of these programs.
I use RegCleaner. I hesitate to recommend this or any other registry cleaner because they can be very dangerous, but so far it has worked for me. Some programs have just refused to let go until I removed the registry entries.
Or you can get a Mac and never have to deal with it. I have both in my home (I'm gradually shifting to all Mac) and the amount of time and aggravation involved in maintaining my Windows machines is enormous. Virtually zero with my Mac.