Lots of good suggestions here for the newbie.

I agree that spending a few extra dollars on better equipment is worth the expense.

Radio: First thing is make sure your instructor is flying the same "mode" you are. Most radios are sold on Mode Two, but there are some old-timers that still fly Mode One. Recommend you learn on Mode Two if possible. The critical item here is that the "sticks" operate the same as the instructor is used to. Usually Mode One flyers can't operate Mode Two and vice versa. As to the brand name, you can always invest in a buddy box to plug into your own TX so don't worry if it's a different brand from the others. It's not until you get into programmable radios that it becomes helpful to know someone who knows how to use them. You'll use both the radio and the receiver in most of your future planes as you step up so get at least a 6 channel. I purchased a JR programmable radio so that I could put more than one plane on the one TX. (8 planes on one TX - each plane could be "memorized" by the program). Cost savings as I only had to buy the receiver and servos for the additional planes (and I only had to carry one TX to the field).

Engine: If you stay within the same size/weight plane, the engine can be transferred from one to the other. Get the better engine. You definitely don't want to be underpowered and you want an engine that is easy to operate and is dependable in flight.

WWII planes are also my interest. You probably won't want to step into the faster models until about your 3rd plane. You could try a Piper Cub (colored in olive drab with military markings). That would qualify for WMWA fly-ins and it's a forgiving 2nd plane. If it is a giant scale, it would also qualify for IMAA warbird meets. Another good model might be Hangar 9's PT-19 ARF.

Hope this all helps... Best of luck with your new hobby...