GParted doesn't work after all. The bootable CD does not understand the video emulation. You are limited to command-line interface.
I also must flame a developer somewhere. They partitioned it in a very stupid way, poor practice to say the least. I'm sure Parallels and Ubuntu teams will gladly blame each other for this. The root partition is the one most likely to be resized, it should be the last partition. That way, you can simply resize using tune2fs. The partition that is the most probable for needing resizing should ALWAYS ALWAYS ALWAYS be the last partition.
Well, time to reinstall. It didn't even ask me how I wanted Ubuntu Server to partition the disk, or choose a size greater than 64GB (just decided that for me, which is annoying as hell)