Well if you are going for crossfire then don't go for the p5q. As for p5e vs. p5e deluxe, they are both great boards. I have heard nothing but good things about both. Still, I would go for the p5e deluxe since it has the newer chipset (X48) and is cheaper. In both cases you will most likely be limited by temps and ram speed so it doesn't matter much.
3.4ghz should be easy assuming you can cool it properly. I have a worse mobo (for quads) than any of those and I can hit 3.7ghz+ stable. Since you don't plan on going very high the bios won't matter very much.
Just stick with the stock bios. Other than added CPU support and possibly bug fixes changing your bios won't make a difference. The only people who change their bios are crazy tweakers and if you have to ask these kinds of questions you aren't one of them.