ok, lemme explain once again:
Modem = dials up to your ISP
Router = this is implemnted on network
if u buy only router, you wont be able to connect to internet (DSL/Cable)
so if u buy router + modem combo (also called ADSL Gateway). you'll get all things into one.
u cannot say weather wired are faster or wireless, as if to get use them for internet only, then wireless and wired acts exactlly same way, as lowest wireless option is B standard so @ 11Mbps (where ur typicsl DSL connection is 512k)
but if you are using your router to switch data batween 2 pcs, then obviously wired is faster.
the thing i'm telling about, (ADSL Gateway) comes as ALL-IN-ONE solution. so that u can connect PC's wireless and wireed as wells.
i'm using US Robotics 9106 (that is ALL-IN-ONE) means, Modem, Router, Switch and Wireless gateway built in.
other ADSL gateways that I have recently tested with all other options and have satisfied me well are:
Belkin (I dont remember the model)
Linksys and U.S Robotisc are most expensive, but Linksys have edge in contribution with Cisco Systems.
but I am using U/S Robotics since days of Dial-Up, and its so well satisfying.
and as wll beautiful design.