I'd recommend you go with Nildram as your ISP - they are the best ISP in the UK. BT Broadband are pretty poor, customer service is dire.
You don't require a PC to test, but you will need to make sure your local exchange supports broadband. 99% do these days.
I'd recommend going wires only (ie. don't be swayed by the ISP supplying you with kit, you will normally dump it anyway), and buying a cheap wireless linksys router/modem, dabs.com for that. You never know when you'll want wireless, so worth having just in case.
This ones' pretty neat.
http://www.dabs.com/productview.aspx?Quicklinx=3QYJ&CategorySelectedId=11177&NavigationKey=11177,4294959958,50468