Here's another idea. Reinstall RH, and when you get to the partitioning bit (DiskDruid?) split your harddisk into 3 partitions:
hda1 = Windows partition
hda5 = Linux's /boot partition. Only need about 5-10Mb?
hda6 = Linux partition
Bear with me:
Configure Lilo so that the only boot option available is Windows and that the timeout is set to a ridiculously small number: 0?
Reboot the computer.
If all works, you will be given an extremely brief Lilo menu, where you can't select anything other than Windows. If Windows boot fine with no errors, then:
Reboot with the RH install CD. Change the hda6 partition to fat32 and format it (keep the hda5 partition, else you'll be buggared again). Do not attempt to install RH, you only want to use the partitioning tool. Reboot the computer without the install CD and you should hopefully be given an extremely brief Lilo menu, where Windows is the only option. Once Windows is up, you should have an extra 'drive' under My Computer.
If you want to get rid of any trace of Linux (including Lilo), may I suggest that you take this opportunity to download XOSL. Install it to the 5-10Mb partition you just created. Unfortunately I am unaware of any way of putting back the plain-vanilla Windows MBR without having to re-install Windows.