You should be aware that if you choose to use a Cable Provider to give you broadband service, you may not be able to go out and buy just any cable modem, whether a product has great reviews or not.
I suggest you contact the Provider, and see what they are using for the service. Afterwards, you can go shopping for a compatible modem, if you wish.
I've never seen a combination dial-up/cable modem (although that doesn't mean it doesn't exist ... I've just never heard of such a device). However, depending on the service in your area, it may be necessary to use both. Some Providers with antiquated one-way cable lines require a dial-up modem to connect to the service before the cable modem kicks in, and in those case, uploading is entirely by the dial-up modem, and downloading through the cable modem.
As for the modems themselves, I've used Com21 DOXport and RCA cable modems without any real difficulty, one with Charter Cable and the other through MediaCom. But all in all, I prefer ADSL over any kind of cable service in my area ... but that's just MY area, and may be an entirely different situation where you live. If I could get a cable line that downloaded ten times as fast as the best xDSL service in my area, then I'd switch. But so far, my opinion is that xDSL service generally has less downtime than cable, at least, from Bellsouth.
You'll hear a lot more about this from other users (if you wish) I imagine. Perhaps you might considering mentioning the general location of where you live, and perhaps someone here can give you an opinion about the type and quality of the broadband services in your area.