Class 6's are OK, even for video but 10's are arguably better. Almost all of mine are 6's if that matters. I have 2 x 10's for when the situation just can't take a chance but I hardly ever need them.
Get youself a couple of 8's (6x) and shoot large JPGs to begin with. Don't try to make the camera do everything it CAN do to begin with. You can't anyway. Learn with it and never forget, AUTO is not a curse word in a tight.
FYI, I'm a man and I have pretty small hands. I like the feel of my T2i and most women seem to prefer it over the larger bodies. Personally, even with my small hands, I still prefer the size of my 60D but that's just me.
"Crop" bodies are probably beyond the scope of what you need to know at this point, really. Seriously. What you need to know is that everything uder $2k is a crop body, basically. Look it up on Wiki if you must, but like I said, it really doesn't matter much to you at this point. Be warned: It's likely only going to confuse you at this point in your career. Walk first and learn to take bigger steps every day.