A full brazillian is just that- everything! You wear a goofy pair of disposable panties, and those are always over the entrance to your vagina- they're shifted from side to side as the waxing is done. Yes, your waxer will probably touch your labia- least mine does, but some might ask you to do it. I'm totally comfortable with it, and there's no way it has a sexual slant at all- unless you're into getting your pubes ripped out by some woman you barely know
It hurts more initially than tweezing, but less overall because so much hair is pulled out at once.
You come in, strip from the waist down, don the panities, then lie down. The waxer comes in, (should) shine a bright light on the area she's working on, then takes wax that has been heated to body temp and smears it on small areas. She then uses a linen strip to press onto the wax and pull it off. If she's professional, she should always pull it off lightning fast, and pull the skin taunt as she does so. The whole thing is over in about twenty to thirty minutes. It's a big adrenaline rush- the first time I did it I was sweating and shaking when it was over, just because of all the endorphins. And yeah, it hurts, but it's WORTH it- like losing your virginity or having a baby. Plus, it's not "hurts so bad I can't stand it." I'd rather be waxed than be nauseated
Before you get a full brazillian, you might want to just get your bikini line (everything that shows when you wear a bikini) done. That way, you can see how good the waxer is, if you like her/him, if you will have a reaction to the wax, and get a nice preview of how smooth you'll be when you get it all done.
Best of luck!