I'm sorry to hear about your crash.

Having posted a similar thread here it seems as though this probably isn't the best solution to the problem. The n900 is substantially heavier than the standalone components would be. And as I'm sure you know, keeping your eyes on the model is pretty important. Although perhaps having a "co-pilot" manning the instruments might work.
I don't think that interference should be much of a problem although it would be important to test this before take-off.

I wonder whether it would be possible to use the gprs radio though. Directly to the laptop, the latency from the cell network would be too great to be useful.

Having the fpv goggles and a hud would be very cool indeed.

</rambling>