Windows failed to start?

So I tried to install a game demo, which finished then asked me if i wanted to restart the computer, so I did. When it starts up it says:

Windos failed to start. A recent hardware or software change may be the cause. To fix the problem:

1. Insert your Windows Installation disc and restart the computer
2. choose your language settings, then click Next
3. Click "repair your computer"

File: \Windows\System32\drivers\sfsync.02.sys

Status: 0xc0000428

Info: Windows cannot verify the difital signature for this file.

If I put in my Vista disc then it comes up with another screen asking If I want to run in Safe mode, run normally etc.

My keyboard won’t work on this screen so I can’t select anything!! What do I do? I really don’t want to have all my stuff wiped so please help…
I would try to do that but my keyboard won’t respond when the screen comes up, so I can’t select anything.

I was just using my computer(Windows Vista) listening to music (on it) while drawing something up for my class until my mouse and keyboard died luckily my BAMBOO pad was working so I "X" out the open windows and restarted my computer. As I was waiting the screen was black and the Windows Failed to start
showed up…and again my keyboard wasn’t working so the timer was over and it automatically went to repair, when that was done it showed again so I turned off my computer and turned it back on suddenly my keyboard worked and I just hit enter on "start windows automatically" then it just started working.

I looked up how to repair this problem but they all say I need the disc to Windows Vista which I don’t have so my question is How do I repair it now?

I tried turning on my laptop and it takes me to a screen which says "Windows failed to start. A recent hardware or software change might be the cause." It then gives me two options, which are "Launch Startup Repair" and "Start Windows Normally." I have tried using both, but either choice makes my computer restart and takes me to the same screen. Alt+Ctrl+Del restarts my computer as well. Escape shuts of the timer to automatic selection. I have tried running both the recovery CD and the support CD, and neither works because Windows is not operating. Do you have any suggestions as to what I should do?
I cannot give the computer any commands via mouse, and it will not respond to any keyboard commands either.

How can finish the installation when my keyboard or mouse will not work. All i need to do is select which language.

I do not want to have to restart the whole installation, just to have the same problem the second time.

I have a second harddrive, with my old OS on it. FYI.

Can you please help? What can I do?
So, is my system going to do the same thing if i start it over?

I’ve recently got a new computer, HP Elite Intel Core i7-920 2.66GHz Desktop Computer. The day i got it, and got it all plugged in, it crashed. For the beginning it was fine, browsing internet, going on msn, surfing the web, etc. all of a sudden it freezes on me, the mouse works and so does the keyboard. however the screen wont let me do anything, therefore i had to manually shut off. I figured the problem was registry corruption. I tried reg-cure and was not able to run it for my computer had a Vista 64bit premium home edition. So i used CCleaner and all worked well. After a while, my computer freezes again, this time i left it idle, and it was in screen saver mode. When i moved my mouse to return to my desktop, the screen freezes and this time so does the mouse. After waiting a bit, i got the blue screen of death. So i turned it off again, and all.. To make a long story short, My computer keeps on freezing for no reason during web-browsing/doing nothing/screen saver/gaming/ etc. Occasionally i would get the blue screen of death, Sometimes from the freeze or for no reason. I have tried Registry clean up, and it still happens. Any tips from people who keep they’re Vista from crashing would help.
I dont believe its any virus or spyware.