It could also be a problem with your RAM, I once had exactly the same problem with a session under WinXP.
Windows/Nuendo needs a quite big RAM-Peak (I guess it’s for graphics?) when displaying the project window after loading the project. If your loaded project (incl. plugins etc) is already near the 2GB-RAM-limit, then there isn´t enough RAM for this display-peak, and Nuendo crashes.
I just went to a Win7-DAW with more accessible RAM, opened the npr without any problem(!), kicked out some plugs and VSTis, and then went back to my old XP/2GB-RAM-DAW. It worked!!
But that was in fact the last project before switching to Win7 completely…
( 
…just wanted to try out one of the new smileys… 
)