Height? I'm assuming that you mean length.
Start with a 5 Weight fly rod sort of like this one.....
http://www.basspro.com/webapp/wcs/stores/servlet/Product_10151_-1_10001_10200176____SearchResults
The second choice is a 7'6" model that should be fairly easy to learn the ropes with. For line, you'll need some 15lb Dacron backing, a weight-forward floating line (5 weight), and a small spool of 4lb leader.
As you are new to this kind of fishing, you want to spool up the first time in reverse. That means you put the flyline on first, and following that with the Dacron backing until the spool is close to full. Once you've done that, take all of the line off the reel onto two spools, and put onto the reel correctly. Going in reverse order will allow you to calculate how much backing your reel will hold.
There are a number of choices as to how to attached the leader to the end of the fly line. What I use is a small eyelet with a barbed shank that is sunk into the end of the fly line. Depending on how finicky the bluegills are, you'll want a leader of between 3' - 5' in length. Whatever length you use, you want to make sure that you can lay the line (fly line and leader) out straight as it touches down on the forward cast.
Baits can be any number of things, but I would start out with a selection of spiders, poppers, and terrestrials. Your local bait shop should give you a good idea of what colors you need.
Lastly, before you hit the water, take the time to practice casting in the backyard. I was taught using a length of yarn and an Uncle standing at my shoulder. I'm sure that you'll find any number of tutorials on you tube that will help you out.