Yep, jes like everone else has said, first you've gotta figure out if both are available in your area. I dislike cable because of the cable loop, normally it's probably not a problem but an example would be a provider allocates say 10 mb bandwidth to X loop, and while X loop has only 10 people on it, durin peek times when all 10 ppl are on it you may notice performance problems. In this example havin 10 ppl share 10 megs of bandwidth is fine, cept, it's more like a couple of hundread. So sure there'll be times when you've got all the bandwidth to yourself an others when your jes tryin to git a web page to load.
I'm on dsl myself, mainly cause there's no cables run out this way (to far from town) an I prefer it this way anyways because my bandwidth is mine alone dependant only on the service providers servers goin out etc. So while there isn't much noticeable difference in performance by the average user you've got a couple of choices to make. If I remember correctly, cable is bandwidth dependant by the loop, an dsl is purchased, I have a couple of em here, ones a 1.3 mb, an the other is 640k so if your area offers dsl at say 256k an cable at loop speed an there's no cost difference, go with the cable. Your liable to end up with better bandwidth at least part of the time. Everthin PC is dependant on what an how you wanna use it for. So don't blow your money if your not gonna use it. If you can get away with a 128k dsl an you don't need more then have at it.
I do have a dial up account, but it's the same as my dsl, I use same account an I work rather closely with my co-op so's I have their numbers etc. I keep it on hand for playin wit my own server an comps secruities, as well as when I work on systems with modems, sometimes it's easier an faster to update em this way via installin a temp nic in em. For you, dump it, if you don't need it drop it.