I have been using both XAMPP and WAMP for 5-6 months and never faced a problem.before that i had IIS also on my system. so our case is very same but i never faced any problem.

just install any one of them and let me know if problem persists.i hope that it would go away.do not install PHP, MySQL and Apache separately at this stage as you may make mistake while configuring.

these package work straight out of box. you do not have to configure a single thing.just run installer and start developing.

and i also suggest that before you install these make sure you have uninstalled previous versions from your system.