Impossible to render!

I am doing a simple living room with a couple of lights,and 640 x 480 Medium settings, a stupid test render , we could say.
It hungs up at the calc... phase with the wait... sign.
As there is no possibility of stoppin' the process. I've got to ctrl alt+del and finish the 3dsmax.
Really dunno what to do!
I can't do anything with Solidrock at this moment, after having done many quite complex works in the last months.
Please help me!
S'il vous plait monsieur...

No, I am using some procedural/ some bitmap based and some Sigershaders (all of them Vray mats!)