Traditionally, do all partitioning from OS/2, have a /boot partition of a few hundred MB's or more, use the advanced install in Ubuntu and when it comes time to setup the partitions, reuse the ones you already formatted rather then letting the Linux partition thing do any partitioning and install Grub in /boot rather then the MBR, and add /boot to Airboot.
Last time I did similar, I also still needed to fix something with DFSee, forget what exactly but it was simple to do, probably the fix CHS values thing.