Endless Paradigm

I'm currently running the i386 version of Intrepid but I'm wanting to upgrade to the Amd64 (64-Bit) version of Jaunty. My problem is that I'm dual booting Windows 7 with Intrepid and if I do a clean install over Intrepid, will it mess up my Grub loader and MBR? If so, how can I fix it if it does?

If it messes up your grub, you can always install/configure grub from pretty much any linux live cd including Ubuntu.

Installation for Ubuntu went perfect. I haven't tested Windows yet but I'm assuming it's okay.