I'm 14 and 5ft 8 if that helps . Would a 40 pound bow be good for me to start off with ?
Compound is the way to go. The key is not spending a ton of money of your first bow. Go to the archery store with the widest selection of bows. Don't tell them you have a price ranges, even though you do. Start with the most expensive bow they have a get a feel for it. then work back to the least expensive. The idea is to get a feel for how the best most expensive bows feel. And then finding a cheap bow that feels a lot like the expensive bows and buy that one. Once you know it's something you're going to stick with you can upgrade your bow. If it's not something your going to stick with then you don't have hundreds maybe thousands of dollars sitting in your closet. It's also a lot easier to get your money back on a entry level bow than an expensive. if you spend 200 bucks on a bow and sell it for $100-$150 your out $50-$100, if you spend $800 on a bow and sell it for $600 bucks, well you can do the math.
Agenda 7 is good, and you need archery accessories for practicing, you can find them on ebay,
http://www.ebay.com/itm/24x-32-Black-Fib...
I'm 14 and 5'8" too! I used a 35lb recurve bow a couple years ago, which was impressive for a 12 year old girl!
If you're starting out, I'd recommend a 35 or 40 pound bow. Why do you want a scope for your first bow?? Try something simple until you get the hang of it.
The Agenda 7 is awesome!
