Will "Try and Decide" allow me to try "GRUB?"

Using the latest 2011 ATH here on XP Pro SP3.

I want to make a dual boot machine using another HD to try and run Ubuntu. I am told that I need to install a program called "Grub" on the XP drive and that will allow me to choose between XP and Ubuntu.

The question is since Grub modifies the Windows MBR, would Try and Decide prevent that change or will it slip right past it?

I don't want to install the silly thing if there is no way to easily remove it. I may find out that Ubuntu isn't for me and I want to go back to just good old XP which does everything I want it to.

I just read on CNET that Windows 8 will NOT allow a boot loader to be installed so you can't run anything else on the machine BUT Win 8! Nice eh?

Thank you in advance,

F Wolf