ubuntu is one of the best linux distros around ... :-)
if you write the bootloader to the partition where u have installed it, you have no problems with master boot record ... :-) then u boot from a Linux boot disk and copy the first 512 bytes of the partition to the floppy.... then you boot in windows you copy the file to a location and modify ur boot ini by adding a line like this "C:linux.bin="My Linux"" then u give a restart :-)
not a big deal ...
also it's easy as that to enable the 3d support, i used to play Return to the Castle:Wolfenstein, and Unreal Tournament 2003 on my Ubuntu system, even it runs faster than in Windows :-)
8)