Cable connections are shared bandwidth, meaning all customers get to share the capacity of the cable, whatever it turns out to be. Charter Communications has three levels of service; the lowest is the equivalent of ISDN, or 128Kbps. That's the option I chose, and it's fast enough. Most of these providers have a maximum upload rate which is considerably slower than the download rate. This means you can download a 10MB file somewhat faster than you can upload a 2 MB file. I've noticed a slight degradation of speed (not terribly inconvenient, but noticeable) after school lets out and on weekends.
DSL connections do not share bandwidth, but you must be located within 18,000 feet of the switching office. The further from that station you are located, the lower the reliability and speed. Practical limits were 13,000 feet about two years ago. Your mileage may vary.
Cable degrades as a function of the number of simultaneous users. DSL does not (signal-wise at least). Cable operators may have a legitimate complaint about more than one computer sharing your connection. DSL providers do not; you're buying a certain bandwidth from them, and you can use it as you please.
DSL can require a little additional trouble. In my area, you must have low-pass filters on each telephone to filter out the digital signal. BellSouth provides them free.
Wireless is cool, but can vary widely within an area. Outside antennae are a big plus. The services I've heard about are generally fast and reliable, but are more expensive than cable or DSL. I don't know whether bandwidth is shared or not, but I think it is. This is offset by the fact that most wireless customers are businesses, and thus they don't mess around trading music and videos or playing online games.
Satellite is a joke. It works, sometimes. Degrades in storms. You must have a telephone line to use it. Your uploads go over the phone line; you download via satellite. And it's too damned expensive for what you get.