The LCD is slightly wider than the OHP lit area, adjusting left or right changes which bit you dont see.
(edit: I see what you were saying. I like to keep the left side of Windows on screen as I use a left side toolbar, hence I chop the right side off)
The only ways to improve this are:
Shrinking the display so it uses less screen area. This wouldnt look good on an LCD though (Edit: not true, fixed in later post).
Get a bigger OHP
Get a 14" LCD.
I dont know if bigger OHP's exist, 14" LCD's are expensive gold dust at XGA res.
Its a tiny sacrifice for the screen you get
