Can I disable GPRS/EDGE/3G and JUST use wifi?

[samuraikc]

So when my friend upgraded to the 3g, he was nice enough to sell me his old 2.0 1st gen iphone for a great price. which i was very happy about. The phone however was not jailbroken or unlocked so I will have to go about that myself, which (if all goes well) will not be a problem via the guides on here. HOWEVER, I am on AT&T and DON'T have the data plan, nor do i want it because I'm a poor college student who can't afford the ridiculous price of 60$ a month. so here is the question:
Is it possible to completely disable the GPRS/EDGE/3G and opt to use wifi exclusively (since I'm surrounded by it 99% of the time) and still have functionality of the phone? If not, then I suppose I just have to be careful to avoid the internet using apps (which would be a major bummer)
Thanks in advance!

[reeko]

once the phone is jailbroken, open cydia or installer, whichever you have installed, and download a programme called "BossPrefs", you can toggle all of your settings and services on and off very easily.

[samuraikc]

once the phone is jailbroken, open cydia or installer, whichever you have installed, and download a programme called "BossPrefs", you can toggle all of your settings and services on and off very easily.

exactly what I was looking for. Thanks a bunch!