Thank you for your input zapatista.
mmm.. yes... valid point about the monitor dot pitch, although with most newer monitors it is less of an issue.
I forgot to mention that this will be used in conjunction with a TrackIR system.
I created a couple images to better illustrate the relation beteween our field of view and the monitor setup. I am not a opthamologist and I'm sure the terms used here are incorrect but here's the gist of it...
I made some assumptions - like the human eye being the equivialnt of a 35mm lens - anyway the square with the 'x' represents the boarder of our visual focus - in hindsight i guess it should have been a circle.
The portrait setup better represents the shape of what human eyes can see. I think I'm leaning towards that setup.
The landscape setup does give an exceptional/exagerated perifial advantage long one axis (mainly horizontal).
In the end I'll experiment with both.