New wireless router - buying advice

I have Virgin 10 mb/s broadband and my wireless router has just packed up (it was a Belkin 54G) so I'm in the market for a new one. What do I need to know?

I looked on eBuyer and they go from £20 to a £100 - what is the difference?

Also, ADSL or DSL?

Also, I have a really old NTL:Home modem, would it be worth buying a combined modem/router, or won't it make a difference?