How good is the shell?
If it's solid, no rust or dents, never crashed, then it might be worth the effort.
Nowt wrong with 5 doors.
If you're mechanically minded (which you didn't mention) then a conversion would be a good option. If you're a beginner, then a better bet would be to just replace the engine with another one exactly the same. A Mk2 GTI engine should be cheap enough to buy and at least then it should be straightforward to pull one out and put the new one in without having to worry about wiring, brakes, gearboxes and stuff.