Honestly, I've installed wamp since older version until this current one on more than 200 machines, and for this version alone on more than 20 machines and never had any problem; however, while installing, I've always had to find out and eliminate some software or setup that might stop or prevent wamp to run properly.
Different people have different things on their computers, and from your post, I try my best to figure out what going on your system and suggest what to do, but most of the time, users only post the problem but not including what they have or think it's might be the problem; as a result, the suggestions don't work at all
If you install wamp on computer that has ONLY Windows, no matter xp or vista, I'm 100% sure that wamp will run w/o any problem; after that, install other softs 1 by 1 such as anti virus, firewall, so on, and after each installation, check to make sure that wamp still run as expected
Have fun,
FREE One A DayFREE PhotoFREE GamesFREE WebsitesFREE Portable GPSFREE WAMP Guides