I decompiled the Gohan model to take a look at the skeleton. I must say, its a tad, uh, bulbous. Do you modelers out there actually use the big skeleton as a reference base or do you make your own for the model?
you can use milkshape for the entire modelling process, skinning (with photoshop also), modelling, animationg, all the good stuff, its really easy once you learn it, however there are always things that sneak up on you on every model you do, no matter what
if you are using milkshpae then it's better to build your own skeleton in my opinion, i can't see a single advantage in using the "valve" skeleton that comes with milky. unless you are not planning to animate, then use a skeleton that already has animations.
but ofcourse if you are using max, then use biped and adjust it to fit the model.