There really isn't a all singing all dancing program that does that, there are various uninstallers etc that claim to do the job but to a degree if you install any complex program you have parts of it on your hard drive until you format & reinstall windows. Be careful what you install is the best advice. Using something like Reg Crawler after you remove a program is I feel the best option click here. That can still leave you with Dll files etc in Windows but it's a brave man or indeed woman that removes those. Something like 'Symantec CleanSweep' from PC World is perhaps something like what you are looking for.