If your Ubuntu won't boot,in a multiple boot system, that means your Grub is somehow affected. There is an amazing program called 'boot-repair', this program restores your Grub program to working condition for most common problems. you can get it here:
I used this program just 2 days ago and it worked flawlessly for me!! I burnt it to a DVD and booted from that DVD. It works.
Once you run the program it should repair your boot issues. Then, since you have a dual boot with windows you will have to clean up the boot manager. follow this manual:
I have followed this manual several times and it makes the login look cool and is quite easy to use. But you have to get the EasyBCD somewhere. I think it's freeware, but don't remember.
Good Luck. As far as computer problems go I wish I had your computer problem :-) if you need any more info let me know.