Best Home Wireless Options?

Just moved to a new flat (rental), where it's not possible to have my desktop hooked up to the router directly, so I'm having to consider the wireless route. Can anyone recommend the best options (with regards to performance and speed) that are available at the moment? PCI wireless card? Simple USB Dongle? Power line networking?

I'm currently with UK ISP Be, who provide a free wireless router, which has been fine so far, but for increased wireless performance, will an third-party router also be necessary?

That router should work fine that they gave you as long as you dont plan to transfer large files over your wireless.

I think I need a charity to sponsor me a router... Im still using a Apple Airport Extreme that looks like a ufo thats like 12 years old or 10 hahahaha.