Ironically, Windows XP runs best on an iMac...and boy Ive been tempted! But its the power footprint I continue to try to balance with the space available inside the droid.
A laptop inside the robot is one way...as well as a DC powered mini-ITX system. The car pcs go ths route, using a special interface that powers the system down before exhausting the batteries.
The stuff I've coded is under Microsoft C# and Visual Basic. I'd hate to take all that and re-do it under Linux.
ubuntu is neat, we have a few tablet PCs running it here at the hospital, just trying it out.