I'm actually using opensuse, not ubuntu, but the distro shouldn't matter. You should be able to run the very latest distros and kernels on that hardware just fine. I run kernel 4.4 (just a few months old) on Mac Pro (4,1)->(5,1) hardware with no issues at all, and that setup is older than yours.
Graphics drivers are usually the biggest problem. Your machine has the Nvidia 320M, if I'm not mistaken. That's what the linux builtin "nouveau" driver calls the NVAF in the Tesla (NV50) family, and you shouldn't have too much trouble with that. Alternatively, once you get the basic install going, you can install the nvidia.com supplied driver, which may work "better" especially for video, but doesn't always play nice with the very latest kernels. If you don't keep up with the latest kernels (note, kernel version is not the same as distro version), you can use the nvidia blob driver and it should be fine.
I don't know the step by details on a macbook pro, but the install generally goes something like: install OSX leaving aside a disk partition for linux, install refind, install ubuntu telling it to NOT reformat the whole drive and to use the partition you set aside. If necessary install Nvidia graphics driver. Done!