Hi Puffer and congratulations on getting a grow on
You're probably best to start off with an indica or indica dominant strain, they don't stretch too much and are normally more forgiving with mistakes than Sativas which can be a little more demanding with thier needs.
Most skunk varieties are considered robust and easy to grow and I can personally vouch for white widow being great for a beginner.
You'll get four big plants in that space, I normally grow roughly one plant per square foot so would have 9 in there but then I only grow with 4 foot of height so keep my plants fairly small.