Generally we'd suggest you buy a card that is compatible instead of messing around trying to get things that won't work started!
I'm not familiar with your card, so it may or may not work, but I had an inbuilt Intel 2200bg in my laptop (which does work)...although I decided to go buy a card that works out of the box instead.
If you're planning to crack WEP then you'll need a card that can "inject" and as not all of them can I'd suggest you go spend $20-30 on one that can.
There's plenty of threads about "Which card to buy?", do a quick forum search and you'll find loads of info...if your laptop's new then make sure you have a Cardbus slot and not an Express slot, (if it's express then buy a USB stick).