Hello.
I am using Fedora Core 3 on a 200 GB drive, and Windows 98 on a 20 GB drive. When I first installed Linux, I wanted it with Windows, and I had the GRUB boot loader installed. Now, whenever I boot my computer, I have to choose, and if I remove the Windows drive, I have problems booting directly from the Linux drive. I now only want to boot Linux (as it is way better :-) and I think that involves removing the boot loader.

For doing this, would I use the fdisk /mbr in windows?

Thanks,
Julien

NO.
This question gets asked all the time - try some searching.
For example

If Linux is not on the primary hard disk e.g. its installed on /dev/hdb then make sure you have changed the entries for it in your /etc/fstab to reflect the fact that it will be /dev/hda when you have removed the windows hard disk. When you have done that reboot and follow the procedure below.

When you remove the Windows drive, boot into your Fedora system using the installation disk and at the first prompt do[list=1][*]linux-rescue[*]enter the details of your fedora root (/) partition[*]chroot /mnt/sysimage[*]grub-install /dev/hda[/list=1]

Make sure you have a live cd at hand just in case you edit something and it results in you not being able boot into your system.