Can't make it with only one
Ad-aware is very good, but you can not use it alone. It will miss things. If you use it in conjunction with Spybot S&D, you will get rid of almost all of it. There are others that are good, too. A perfect example is the DSO exploit. You will need a specialized purchased software to get rid of this problem because it changes the registry unless you want to mess with your registry that may or may not cripple your computer.