Depends on the size of your house or desired operating area really. I would get a 108MB/Sec modem/router though as there is no premium these days. Netgear (check out their MIMO routers) and no doubt several others are now claiming large increases in range and consequent operating speed with their latest offerings, but wireless is such a growth area that I would expect most major manufacturers to be offering similar.
Of course, the old carrot of offering you a free PCMCIA/USB/Dongle is still there on many products, so a bargain is there to be had.
Some newer routers and similar, are now including phone sockets for Voice over IP or VoIP telphony. Do you have any interest in this area? If so, you might check if any prospective purchase has provision for the odd telling bone to be plugged in.
Best location for a router is high and central to operating area, but a really great way of getting conned at the last fence, is to find that you need longer patch cables, etc. etc. and then hop off to the nearest P*World, where they will be delighted to relieve you of more cash. There are much less expensive options :-)
Just having a horrible thought - check on what you really need. Although routers, gateways and modems can all look alike, they all do different jobs. If you need just a router, then fine - but modem routers are often the thing that is needed. I know of 3 peeps so far that have bought routers and then had to go back and buy modems as well, or swap their original purchase. My own Netgear is an all in one solution and I am very happy with it.
Conan