What is the best way to install trim molding around a window frame on the drywall or sheetrock. Should I use finishing nails and should I also glue the trim too?

You Can Use Finish Nails , Hand Drive Nails Or Gun Nails, As For The Size Of Nail, A 4 Penny Finish For The Inside Edge Will Be Fine And A 8 Penny For The Outside Edge Will Work, No Need For Glue Except For The 45 Degree Joints Of The Trim Your Using

What is the best way to install trim molding around a window frame on the drywall or sheetrock. Should I use finishing nails and should I also glue the trim too?
finish nails usually suffice... the window is set into a framed opening (2x4's).. the sheetrock is face nailed to the studs... depending on the width of the trim moulding striking the stud is usually no problem... locate the studs/layout the moulding nailing... gluing the miter corners is sometimes advised... especially if it is paint grade trim... it helps to side nail the miter... generally keep your face nailing in 2" from the boards end otherwise the moulding may split... if it is hardwwod trim you may have to predrill for the nails... set the heads with a nail punch