I just installed Wampserver 2.1 on my windows 7 64bit computer and the icon that should turn green, turns orange, saying that the server is not ready.
The result is
Check each service individually. MySQL uses port 3360 so that might be blocked as well.
On a personal note, I've been finding WAMP a problem after version 2.0i, so I switched to a Linux VM or even another computer running linux for my PHP development.
Try EasyPHP since you can install that onto a USB drive so you can keep the "WAMP" with you.