I have to install Dual Linux OS

Hi buddies,

we have a Dell Server 2900…we are planning to install dual Linus OS with Debian & RHEL 4 in the same server.we want to know which one is the right way to install the OS weather its Debian or RHEL 4 because we kindly want to know that after Linux installation with Debian will support for grub or not / Is it possible to install dual Linux Os on the same system or not we a question like this which i have to install first its Debian/RHEL 4 so it would support for both without any interruption.This is immediate requirement to setup the server.so kindly i need some help form the buddies its appreciable and thankful for us.

Thanks in Advance,
Allabux.A