|We need to determine whether this is a hardware or a Windows software freeze up.|
Tap F8 key while it is booting and see if it produces the startup menu.
If it does, then at least F8 is working. In which case try selecting Safe Mode and if it works then check out your keyboard from there.
If F8 doesn't appear to be working then you could attempt to go to BIOS. I'm not sure which key it is on your Gateway but watch the screen and it should mention "setup" and the key required - usually it is F1 or F2. If you get there then don't do anything, just power off - I only want to know if the keys work.
Electrical and mechanical things are always working before they stop working, so that's not so strange LOL.
Always pop back and let us know the outcome - thanks