are you sure dvd architect doesn't? I've never used it, but it's sucky if it doesn't.
VBR would be best, but if it looks ok all the way through (and i mean all the way) with cbr at 4mbps, then go for it.
AMD Athlon 1700 (@2200mhz from 1466 sod the noise!) - 768mb pc3200 - 200GB Maxtor - Pioneer 106 - GF4 Ti4200 - twinhan/visionplus pci dvb-t - random pci analogue tv tuner - A7v600-x (to replace the a7n8x-d that died...) - random 17\" CRT
Sony STR-DE425 & Eltax c205s;
xBox w/20GB HDD- executer 2.3b;
xBox - standard;
Konica/Minolta dimage z10 w/2x512mb SD;
A silly amount of Cat-5 and usb cables