Glad to hear you're thinking of chucking some fluff.
I do the majority of my fly fishing at Moorhall Reservoir near Wharncliffe Side, it's quite a big water and gets a fair bit of wind blowing through. I usually use a 9ft 6'' weight 7, I can get a good distance with this set up and the wind usually doesn't bother me too much. It's quite a heavy set up but it still works perfectly well whether you're chucking out at distance into the wind or presenting a small dry on a still summers evening.
For fishing the smaller commercials I would probably use around a 9ft 6'' weight 4 or 5, but you'd be absolutely fine with the weight 6 or 7 set up.
A good tip for learning to cast, especially for distance, is to use a weight 8 line with a 7 weight rod, or a 6 weight line with a 5 weight rod, you get the idea, this helped me when I was starting out. Also, always pick a target to cast to that is above and beyond where you actually want to cast, this will keep the line up and allow the leader and fly to straighten out before hitting the water, this was one of the best tips when I was learning to cast.
Another thing would be line choice, I really think it's worth spending a few more quid and getting yourself a decent line. A floating line should suffice for most of you smaller shallow commercials, for reservoirs you might want to invest in an intermediate or sinking, depending on what you're doing.
I hope some of this helps. Once you're geared up give me a shout and we'll have to get out somewhere.
