![][1] Staraptor @Leftovers Trait: Intimidate - Wing Attack/Fly- STAB - Close Combat- Coverage - Heat Wave- Coverage - Swift/Tail Wind- STAB [1]: http://img.pokemondb.net/sprites/diamond-pearl/normal/staraptor.png
I'd say Wing Attack because you could do more damage in two turns that one Fly. Just a note: Heat Wave wouldn't be too good on Staraptor
I'd say fly because it is more powerful and it gives you a turn of being protected, whereas wing attack you could fit two of these attacks instead of one fly, i'd use fly, but its up to you :D
Go for Fly, it can be handy for unexpected situations, for example Vs. Slaking. =) It can be also used to deal with those who use Protect most of the time, as we know protect can fail on its 2nd time of use. I used Fly to deal with a Yanmega using protect for speed boost on random match up. It can be also used to evade two turn attacks that needs to charge first like solarbeam.