OK, definitely go with the Nosram engine (it's not realy made by Nosram, it's made by LRP, as are the Thunder Tiger engines, I believe, it may even be the exact same engine, even if it isn't I have experience with Nosram engines, they are good).

Radio - Futaba 3pm with ONE servo ($100, don't know how much in blighty, but can't be that much more) put this default servo on the throttle/brake. All radios come with compatible receiver unless they say TX ONLY.
Servo, most torque you can afford, 150oz-in or more, don't worry too much about the speed of it at first, you can always get a pro one later, the torque is the important thing.

Tube? Don't know what you mean, but you will still need the following...

Hex wrenches (maybe you already ahav a lot of tools??)
Receiver battery (6v stick for the Xray) - (20 quid??)
Peak charger
Glow ignitor (15 quid)
Fuel.
Cross wrench (ask your LHS, important but cheap)

That should do it. Maybe some spare glow plugs, etc...