My brothers computer is on Orange broad band.
His internet is connected via Ethernet cable, but explorer refuses to recognise it saying its disconnected, now i've had this before but solved it can remember how though?

Any help as he's gonna buy a new one, and i don't want him to waste his money.
Buy a new what? PC? Router? ISP? Cable? Network card?
Anyway, that won't fix the problem.
Try Start -> My Computer, My Network places (on the left under Other Places), View Network connections (on the left under Network Tasks).
Under LAN or high speed internet, there should be Local Area Connection. If it says disabled, then you need to right click and enable it. If it says connected, then that isn't the problem, if it says network cable unplugged then it could be the cable or the network card or the router that is at fault!
Let me know what it says and I'll diagnose further.