After trying the other things, if they don't work, check to see if there are updated Vista drivers for your motherboard. I had the same problem early on, and that fixed it for me.
And if you set that number in the registry, it should be lower than 15000. I'd set it at 5000 or something. 15000 means it will wait 15 seconds before it force closes something. 5000 means it will wait 5 seconds. But always remember to back up your registry when working with it, and be very, very careful.