I don't follow the herd I go my own way,
I wear Pearl Izumi Elite In-R-Cool 'Cut' Shorts ,,,

Yeah they are spandex and look like roadie shorts but they don't hang up on the seat as I am in and out of the saddle constantly.
And they don't make noise rubbing away, they move with me.

If you gotta go baggy try 3/4 length, they are longer and will be less likely to hang up.
Good regular mtb shorts, I liked my Bontager's and Fox shorts are good..
Definitely get shorts that have a removable liner, then you can wear your road kit underneath, your most likely going to want the padding..

Yeah from your post OP,,,If I was there I'd prolly be the only one in spandex but mountain biking has made me so good looking I carry mace to fend off the women so the guys would just be jealous

Go here biker, for the best:::::::::::
http://www.troyleedesigns.com/

The Skyline Shorts are top shelf....