I have found the 757 easy to fly and very enjoyable.  My flight sim is P3Dv4.3.  I recommend first using SHIFT-2 and selecting EP, then turning on external power from the overhead panel.  Next, press CTRL-E to start the engines.  Flight plans can be created using the flight planner and loaded into the CDU.  I highly recommend reading the well written manuals for further info.   :) :)