My advice is here however, not to install Ubuntu since its footprint on the hardware is rather big compared to other Linux distro's.
My personal favorite is Xubuntu x64. Works perfectly with RetroPie but has a smaller footprint, thus leaving more for RetroPie to use, thus giving a better performance for emulation. N64 games run better on the same hardware with Xubuntu, compared to Ubuntu.
Nice thing about Xubuntu is that it's very flexible and performs great on older hardware, whereas Ubuntu requires more power. The biggest difference between Ubuntu and Xubuntu is the desktop interface, but that one can really consume your hardware.