Magnepan, Ohm, Spatial or ??

I would think due to room size and placement limitations that planars and OB would be out. 

The Ohm Tall 1000's could work and they offer a generous home trial period. 

I heard Wharfdale's Diamond 10.7 several months ago and thought they decent little speakers. 

You could always go the bookshelf route too. Lots of great choices. 

Do you have a budget you're working with?

OB speakers will work in that room as long as you can get them at least 3 ft off the front wall.

Oz

Budget is probably around $3,000-$3,500ish.  It is sort of a strange room. 

The Kef R3 plus a sub or two I think would work well. What are your other components?