My current partition is around 7gb, but I have 200gb of unused space. I'd like to resize this partition to include some of that space. Since I have no other partitions with operating systems on them, how can I resize the partition I'm currently using?
In order to resize a partition, the partition must be unmounted, that means that you cannot resize from your current installation. You will need to boot with a live CD/USB (such as the one you used to install ubuntu)
Boot into a live ubuntu and fire up