What partition table does the Ubuntu 12.04 live CD installer make? Or can you choose that?
Or should I use Gparted when I make the partitions for best compatibility?
As pointed out by Jai. Ubuntu does use Gparted in the background to partition the drives
As its installing you will see a screen similar to this
It may also have additional options such as install along side Windows if you already have Windows installed. If you select "Something Else" the next screen you see will be similar to this
And you can configure your drives and partitions how you want.
Note: These screen shots came from a totally blank machine running inside Virtualbox so the images you see are likely to be a little different.
The Ubuntu Live CD also uses Gparted partition Manager only while installing Ubuntu & in the partition stage Ubuntu will give you three choices in the installation process. If you dont like those then you can choose custom choice & that will be the last selection. There you can create your partition manually.