As far as the pickups.. The Bridge pickup is the one you'll want to use to get more treble on your sound, so for a good metal tone or lead sound you'll definately want to use the bridge pickup.
The Middle pickup is the one you want to use for blues, it's got a more tinny sound to it. Listen to some of Dire Straits stuff, thats more of a middle pickup sound. I don't know anyone who uses distortion with the mid pickup.
The neck pickup is more mid and bassy, good for a soft lead tone, not really a good choice for heavy metal riffs. Unless you have a decent neck pickup the sound probably wont be as clear and defined.
Then again im basing the above on a HSH setup. If you have a fender strat its gonna generally be a less beefy sound on the Bridge and Neck, given that they use SSS. Humbuckers are a more fuller heavy sound while the single coils are more defined bluesy type stuff.
Ok...I just realised i'm not very good at explaining things :D