To paraphrase JFK, we do not choose to install Ubuntu, or any other form of Linux because it is easy, we install it because it is hard.
That said, it’s not as hard as it could be, unless you install the wrong version. First, I installed the 32-bit version, which was what was recommended on the Ubuntu site. Everything went pretty well until I tried running Minecraft. I got as far as the create a new world screen, then it crashed. The solution: Install the 64-bit version. (The issue in this case is that fglrx, the proprietary video drivers for my video card, don’t play well with Java when you use 32 bit Ubuntu. 64 bit works.)
Of course, this lead down a Google rabbit-hole. I messed up the re-install because I didn’t specify an EFI bootloader partition, and the Ubuntu installer didn’t warn me that it wouldn’t work. (You get the No operating system found message.) Then some sort of graphics misconfiguration meant that when it tried to boot into Unity, (which I already hate) all I got was a blank screen. Three or four reboots later, this problem somehow sorted itself out, whereupon I disabled Unity, then apt-got fglrx, and after that, everything seemed to work fine. That still left replacing OpenJDK with Sun’s JRE. (apt-get remove openjdk-6-jre openjdk-6-jre-headless. That seemed to remove everything that needed to be removed.) Minecraft now runs, (I think. I did get a crash which corrupted my save file, but that was after messing with graphics options pretty intensely for five minutes or so.) It’s not perfect. Being Java, it seems like GCs cause stuttering, but being able to play it at all on what’s basically a slightly beefier netbook it kinda cool.
Now, I just need to install Eclipse and the Android SDK, and I can strop using my lapburney Macbook!