I think my hardest install was on a machine I'm now using as a server:

I had Windows 98 SE on it, and then installed Mandrake 7.1 on it (This wasyears ago obviously) and then I had extra drive space left, so I made a new partition for FreeBSD 4.0.

3 OSs on one disk, and once BSD was installed Windows wouldn't boot anymore. Whole thing had crapped out.

By the way if you don't want to type startx, you can do this:

init 4

That loads up the KDM display.