Don't bother. The next operating system that you install on the hard drive will almost certainly wipe out the MBR that contains GRUB you're noticing right now.
If you really must do it, boot up the Linspire CD, obtain a root prompt, and enter the following:
dd if=/dev/zero of=/dev/sda bs=512 count=1
(replace /dev/sda with the device of your hard drive, if necessary)
Warning: this will wipe out your entire MBR -- this includes both GRUB AND all your partitions on the drive. Only execute this command if there is nothing of importance on the hard drive.
John A
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John is right, the short of it is that you left the MBR intact but changed the partition scheme so the original boot record isn't valid. Take his steps to correct the current boot record or just put a new one on it.
OlyComputers
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