I have two versions of grub. One from an old distro of Debian Sarge, and one from an old version of Ubuntu. Nether of distros work anymore, but I keep getting the option, with the last one being Windows, which is the only thing currently working. I want to get rid of the two corrupt distros, which I don't think will be a problem, and install a modern distro. I just don't want any more grubs. I know I did this before. I just can't remember how.

Install your new distro over top of one of the ones you want to remove. Boot the new distro and format the partition of the other distro you want removed. Once this is done, open a terminal and type: sudo update-grub

You need to install a new system and use its bootloader as suggested. Removing Grub before installing a new system is going to give you an unbootable machine as it is extremely unlikely your windows bootloader is booting both Linux systems. If you have the windows installation medium for whichever windows version you have you could install windows code to the MBR, that is, if you are using an MBR system. When you install another Linux system you will likely need to use the Grub bootloader to boot both as using windows is more complicated.

Hi.

Back up your important data and yes, just install a* new GNU\Linux; wipe the others (I would do microcoughed's too but whatever ) then install the distro* it will reinstall GRUB wiping the old one... and runs:to boot.