First, don't do dial up. Really, there's no point to it if you have DSL or Cable available, even at a premium price. As a law student, you'll likely spend some time researching online, either at the library or from the convenience of your home, and the costs of DSL or Cable will be well-worth the added convenience. Don't believe the commercials on TV. Dial-up is still dial up...there's only so much bandwidth allocated to each commercial, analog phone line, and nothing net-zero or any other company does will change that.
So, really, it all comes down to what packages and availability you get with Cable or DSL. "Wireless" is just a function of the router that you'll have to buy (router with wireless capability like Linksys WRT54GS or similar) to use in conjunction with your DSL or Cable service (which, by the way, can be encrypted so that no one else can use it, a feature that your neighbor obviously overlooked).