Recovering from GRUB effects of "garbled" install

[Richard Owlett]

I took the prompts issued by the installer included on 
"live" edition of Ubuntu 10.10 *TOO* literally. I was 
working on a Windows machine on which I had no intention 
whatsoever to have any Linux distro whatsoever.

I thought I was installing everything to a USB stick. It 
accepted me designating the stick as target. When asked if 
the whole device was to be used I responded affirmatively. I 
expected a Linux install on the USB stick that I could run 
on any machine that could boot to a USB device (all my 
hardware has the ability).

What I _got_ however was Ubuntu on the USB stick and GRUB 
1.99 on my hard drive. This could have been an annoyance 
only. *EXCEPT* GRUB has evidently been configured to default 
to Ubuntu with the side effect of failing to boot any OS if 
the USB stick is not inserted at boot time.

Questions:
1. Can I get rid of GRUB completely from my hard drive?
2. Failing that, can I have the existing WinXP be the 
default OS.
   Related, I must get rid of requirement that the USB 
stick be present.

I raised the question on a Ubuntu forum and got a confused 
mishmash of responses. A primary problem was responders 
ignoring  differences between GRUB Legacy and GRUB2.

HELP ;/
Though a Linux newbie I'm not scared of the command line as 
I date back to before CPM-80.

TIA