If you are targeting BG I would use a 2 or 3 weight rod....7-9 ft. in length. If you are tossing flies that small you can use a longer 7 or 9 ft. leader.
A 5 weight might pull a 6-7# LMB out of a brush pile but it won't be able to cast big hairy flies very well.....maybe with a 2 ft. level leader you could give it a try.
Remember, a fly rod uses the weight of the line to get the fly out there, not the weight of the fly itself. Maybe my casting skills are lacking, but I can't cast a wet 6 inch long rabbit strip fly with dumbbell eyes for weight with a 5 weight rod.
And yes, when starting as a new flycaster, a 9 foot 5 or 6 weight rod is good to learn on. I don't think you want the action to be very fast however, something in a medium action is good. BM61.
