The x64 version of Ubuntu 5.10 worked on my computer, and it asked politely wether or not to install grub in my mbr. Their installer needs a LOT of work still. It has nowhere the control that SuSE’s Yast2 has. Even though I was able to get grub installed in my root partition I had to guess the location, there was no menu. What it needs more than to be graphical is to have mouse support.
Once installed Ubuntu was actually pretty good, not the easiest distro to use, but the easiest one to install software on. Its implilmentation of apt-get is flawless, and for more common programs there is a simpler installer. One of the things that absolutely rocks about gnome is its drag and drop support. Things like themes, widgets, and icon packs can be installed just by dragging it onto the window that selects the item you happen to be dragging.
A few problems after installation include the difficulty in installing nVidia drivers, which can be done, but is a royal pain. The most updated version of Firefox you can get via Synaptic is 1.07, and attempting to install FF 1.5 only served to mess up the system. The 32-bit compatibility seems only to exist when it wants to, no 32-bit packages will install at all, and manual installation works maybe 10% of the time.
At least you can get drivers to install. Everytime I dpkg-reconfigure xserver-xorg and select fglrx, I’m dumped to a command line on repoot with a message saying that it can’t connect to the server (or something like that).