Hi Yvonne, honestly I would get the biggest storage system (hard drive) you can afford - every time we upgrade a laptop we get the most GB storage possible.
As to Bluetooth - it's a good thing to have and is pretty standard these days - it allows you to wirelessly work with or sync any other Bluetooth devices with your computer (like cel phone, PDA, Blackberry, wireless head phones, wireless mouse - etc.)
A good current laptop will already have a wireless modem in it (you shouldn't need to purchase a wireless adapter card sep.) - and I couldn't tell by your post if you were asking if you needed it as a bought accessory or if it was included in the computer you were looking at. A wireless card will allow you to connect to the internet without a cable (assuming you have purchased and installed a wireless router - or requested one from your hosting company)
Even with a huge hard drive, back up storage is still important (just in case) and you should be looking at 'external hard drives' - ours is about 120 GB I think and I believe we paid about $90 for it.
As to screen size on the laptop - that's up to your preference. I had and loved a smaller, traditional screen at about 13 inches for ages and really got grumpy when I realized the model of laptop I wanted only came in widescreen. But now that I'm on it I love it and wouldn't go back - it's just more comfortable for me now and I don't even notice anymore that I'm on a 'widescreen'.
I also made the switch from XP to Vista on my current laptop and grouched about that

(Can you tell I don't initially always appreciate change?) but again, I am loving Vista. I'd recommend if you can get a computer that comes with Vista Business to go for that.
If you want to post a link to the laptop you're thinking of buying I'd be happy to ask Hamid to take a look and see if you're getting your money's worth - he's our tech expert in the house and I am always happy that he makes the technology decisions (although I usually whine about which color and size I want.)
Check out
www.newegg.com for laptops - that's where we bought our most recent two these past few months (as well as our external hard drive, wireless modem, and a stereo to boot!) and have found great prices on the most decked out modern models plus there are reviews from users who've purchased the items so you can see what other people like and didn't like.