Re-installing linux on Dual Booting machine
 

I currently dual boot my machine with Windows 8 and Backtrack. Backtrack has been giving me a lot of trouble and can't recognize that i use 2 graphics cards so startx will not work. I would like to re-install linux (maybe ubuntu?). I was wondering if i could simply wipe the backtrack partition as un-allocated space and then just install it there and not screw up the GRUB Boot manager. Would that be possible? I know that when you install linux it makes GRUB the default boot manager but i'm not sure if it will install it twice and then screw up my machine.

Any advice would be appreciated on how to go about doing this.

Thank you!

Wiping the partition is the thing that screws up the boot-manager, but that would not be a problem, if you install a different distro it will replace the boot-manager with its own Grub anyways, so just go ahead and install whatever distro you want.

There shouldn't be any issue like the way you are proceeding. Carry on.