I have a video job which will be displayed via a Dell projector. This projector has a self contained DVD player (does not use PC).
What "field order" setting should I choose in my project properties (lower, upper or none)?
You should set your field order to match your footage (lower field first for 60i DV, Upper field first for 60i HDV - sorry I only know NTSC).
As for the projector - I would probably keep the field order the same when rendering to mpeg-2 and the projector should be able to handle it fine. You can try de-interlacing and making the footage progressive and in some cases this can give better results but in many cases it doesn't make much of a difference. Really depends on the projector and your ability/desire to tweak the footage.