restaurant - restoran
closed - fèmen
waitress - sèvez, manmzèl, (or) sèvant
please wait for customer service - tanpri tann pou yo sèvi ou.
yes. check prepositions in the following blogs:
http://sweetcoconuts.blogspot.com/2010/10/exercise-33-going-places-part-2.html
http://sweetcoconuts.blogspot.com/2010/10/exercise-31-going-places.html
http://sweetcoconuts.blogspot.com/2010/10/exercise-35-going-home.html
http://sweetcoconuts.blogspot.com/2010/03/list-of-most-frequently-used.html
I think the're both strong contenders.
Manigat for stability
Martelly for change