I will highly recommend the Linksys BEFW11S4 Router... currently ~£42 on
http://www.ebuyer.co.uk
A guy who worked where I am got a Belkin (from PC World believe it or not - PC World
must get bribed to sell more Belkin stuff!) and he says its great. But I have heard of people say they're not so great. I think its the luck of the draw to be honest...
Many say Linksys' router firmware is weak... but many have said its improving since Cisco Systems have been stamping their impressions onto the kit.
I've heard of some people having trouble with Netgear stuff too... and I find their LAN cards (although pretty cheap and decent quality), they can die pretty miserably.
All in all though, I'd go for the Linksys... but as I have one, I'm biased :p
Alternatively, get a 3com TX-905C NIC (I got one off ebay for £5 + £1 P&P) - have an onboard dedicated processor to minimalise (sp?) any usage of the main CPU to process it's data.