[Help] A few basic questions

Right now I have ATT with a minutes plan and text messaging plan. Here are my questions:

1. If I buy a first generation iphone, it can be easily unlocked and works with the version 2 firmware, right? I have lots of experience with computers by the way.
2. I won't have to get the data plan because ATT won't even know I have an iphone, right? (I don't need a data plan because I'm on a college campus and WiFi is everywhere).
3. Is there a way to block data on the iphone so I don't accidentally use the data network and end up with a very expensive phone bill?

Anything else I should know before I go buy an iphone 2g?

Thanks!

Hi, im in the same possition as you...know my way around computers but lost when it comes to the iphone,

Would be useful to know the answer to these questions too! Also....anybody know how to figure out which version iphone you have? I keep seeing people calling them 1st gen, etc and dont know what different ones there are?

1. Yes
2. No, you wont
3. Yes, there is
4. 1st gen has a metal back. The other version is called the 3G (it has 3rd generation mobile networking, i.e. fast internet).

Now from now on, search the forum before you ask!