A question about professions and stats.

I really want to make a Necro/War, but I'm confused on how the two types of skills would work together. I'm also confused about equipment. Can any profession use any kind of weapon? I know I'm limited to necro armor, but will I be able to use any weapon available to a warrior too? If not, it sorta renders some of the warrior skills useless. Also, does one profession start off with more health/energy than another?

You can use any weapon. If you don't meet any prerequisites the weapon might have, you will not be very effective (doing minimal damage). In the early portion of the game, most weapons do not have any prerequisites and can be used by all characters.

I believe all charcters get the same amount of health, but energy varies by class -- i.e. spellcasters get more energy than warrior/rangers.