First: Congrats on obtaining one of the finest RPG's ever crafted. I know you'll enjoy it, even without the cloth maps! [img]smile.gif[/img]
Now then, as to your question. No, you don't have to know anything about the previous wizardys to thoroughly enjoy the game. It is in fact made with the assumption that everyone is playing it from a "newbie" perspective. Everything is well laid out, and there are only a couple of obscure "old wiz" references in there, and you can ask us about those!
You don't have to be a serious RPG-er to enjoy it, either. Although if you aren't, then modifying your characters stats when you level up might give you some problems. Again, ask us here on this board. We'd be glad to help!
Now, go play. [img]smile.gif[/img]