Update to grub2 breaks everything

[address@hidden]

I have a netbook that came with Windows installed. I want to use Ubuntu, but 
keep
Windows as a fallback.

I created a live USB of Ubuntu Netbook Remix 10.04. It worked well. I then ran
the Ubuntu update manager. During installation of the downloaded updates, I was
told that grub2 was being upgraded and asked questions about devices to which to
install grub2. I thought that the correct answer was just the USB drive. It
wasn't. The updating failed and I couldn't boot into UNR anymore.

I started again (in other words, recreated the live USB and reran the Ubuntu
update manager) and chose all devices shown. That wasn't the right answer 
either.

I thought maybe the problem was with UNR, so I tried the regular Ubuntu 10.04 on
live USB. Exactly the same result--all worked before running the update manager,
nothing after.

Next, I installed regular Ubuntu 10.04 to the hard disk of the netbook, using
Wubi. Exactly the same result when I used the Ubuntu update manager.

I Googled and found many people with similar problems, but no solutions I could
follow.

Is there yet a definitive solution to this problem? Some simple instructions I
can follow myself? Would it be adequate just to refuse the offered update to
grub2 when I run the Ubuntu update manager? Alternatively, can I downgrade to 
the
old grub before running the Ubuntu update manager, since I've never had problems
with the old grub?

Leslie
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