Ubuntu :: Cannot Get Computer To Boot Into ANY Operating System?

I've been using Ubuntu Netbook edition on my Asus eee pc 1005HA, dual-booting with Windows 7.Things have been fine with it for a month or two. However, I've now run into some trouble with Grub2 and the MBR, and I cannot get my computer to boot into ANY operating system. Right now I'm booting from the Ubuntu installation CD to "try Ubuntu" -- it's the only way I can use my computer at all.

I have looked through the forums and googled, and already tried several methods of fixing Grub2, none of which have worked so far. Here's the situation: I wanted to disable / uninstall Grub2, so that the computer would boot as normal into Windows 7, to fix some problems and then reinstall Grub2 later. To do this I just went to the Windows System Repair environment, opened the command prompt, and entered the two commands "bootrec /fixmbr" and "bootrec /fixboot" with the understanding that this would reset the Windows control of booting, and remove Grub2's control. The result was that my computer cannot boot properly at all. No Windows and no Grub2.

So far I've tried to fix this by using the Super Grub Disk to try to use the auto-repair feature, which failed. I've also tried in various ways to reinstall / repair / update Grub by using the Terminal in Ubuntu (through the "try Ubuntu" CD), but so far none of the methods I've found have worked. If anyone could explain or direct me to a step-by-step of how to repair the MBR and install Grub2 from scratch,