You've got a bench that's seven feet high? Confusing. If it's what it sounds like, unless you're planning on growing some seriously big ass plants, I'd put the lights below the bench.

Really, you need to give a little more info. You can install pretty much any kind of light, anywhere. In a closet that's 5' x 2', you've got 10 sq. ft. of floor space. That's a lot. Because it's an irregular shape, you might be better off with 2 150w HPS/MH. To light space that big, you're going to need a ton of CFLs...at least twenty of the 23 to 26 w bulbs. If you're determined to use flouros, I suggest getting a 4 bulb 4' t5 setup. You should post how many plants you want to flower, if you want or need to use the whole closet, ventilation, etc., to get better answers