Do you have a network at home banjo?
WDTV Live hub would get my vote. I have the Live (non hub) and its really good.
Another alternative would be a DLNA device like BD player (LG BX50) which will play files over your network, but then the WDTV will do that.
You seem to be hung up on the usb2 transfers. You laptop must be pretty cruddy if you think that will be your slowdown. I transfer data across my usb external and pc at approx. 30MBps.
Not staying at home at the moment, i do have 10-18mb/s broadband but i don't want to rely on this...
If i was to use the network would it have an impact others connected to the internet?
WDTV Live... would this just access the videos from my laptop then play them on the tv via ethernet or wireless...