Engine: If you want a 2 stroke, the OS 120 is most likely the best bet. If you want a 4 stroke, a YS 110 is the way to go. It's personal preference, 2 or 4 stroke. If you're a beginner practicing you need reliability over performance edge. Therefore I'd have to say the OS because the YS will cause a lot of vibration. This is ok if you're used to it, but just realize it equals more maintenance on the airframe over the long run.

Servos: all you can afford. If you want a clean and true flying pattern plane, use servos with good centering and about 80+ inch/ozs of torque for everything except the rudder. use at least 150+ in ozs there.

I won't recommend exact servos, just look around. Don't skimp, or you'll hate life. Just my 2 cents worth.

-Mike