[newbie] How to uninstall GRUB OS switcher

[DeadlyMewtwo]

Hey all. I'm having a big, big problem. I can uninstall LM just fine, but
after I do I'm stuck with a computer that refuses to boot! It comes up with
that GRUB program, but it can't boot Windoze! I have to reinstall LM in order
to boot to Windoze again!
Please help!
Is there a way I can get it to go back to booting straight to Windoze?

Please tell me because I need to get this back to Windoze because I will be
getting a more powerful comp and giving this one to my mom's office.

Thank you all in advance!