Already have Airport Extreme: which Plusnet hardware to go with it?

[#1]

I placed my order for Plusnet broadband yesterday. I already own a new Airport Extreme base station and need a modem to go with it. I have the choice of the wired and wireless modem routers from Plusnet, but I'm unsure which is the best to go for. My concern is that by taking the wireless router I will somehow compromise the functionality of the Airport Extreme base station. My suspicion is that the wired modem router presents a simpler solution. But that's not based on any firm knowledge.
Can anyone advise?
Many thanks.

[#2]

The wired router/modem is probably sufficient as your Airport will be looking after the wireless connectivity aspect of things (which is the main differentiator between the two Thomson models). Not sure whether or not you're going to need to set the router/modem up in bridge mode either having never used an Airport base station myself?