Vegas 4.0 has been working splendidly. One day it decided it would no longer render anything besides DV codec. whenever I try any other format, I get to a random percentage, then it tells me:
Hahaaaa! I have found the solution, which may be helpful to any of y'all should you encounter similar problems.
After Vegas crashed during a render AGAIN I checked the CPU temp and it was a lovely 84 degrees celsius! hooray! and by hooray I mean Christ NO! Anyway, a cooling solution has brought the CPU down to stable temperatures, and I can render once again.