If your begginging, it doesnt really matter. DB classic may be better to start with, but Pro would just start you off with the better (possibly harder) program. But if its already ordered there is no need to worry about it.
One of my fav. demos ever from DB was the Equilibrium demo(s) and they were made way before DB pro, so I think classic is good enough to start with
Good luck learning DB, it really isnt hard at all. Im only 14, and Ive been using DB for about 3/4 a year, and I understand it quite well.
Contact me on the instant messengers below my post (msn is TheBedroomProgrammer@hotmail.com the button doesnt work lol) if you need help. I already have loads of people ask me stuff every day, its no biggy
Good luck!
RPGamer