Few questions

I play a paladin, and I'd like to know a few things.

First, one of my party members told me to stay still so I wouldn't slow the DPSes down. Would anybody else recommend this, or include when you're avoiding AoE attacks? (The latter doesn't include AoE attacks that will kill you, like one of Titan's)

Second, I should prioritize VIT and Parry, right?

And thirdly, when people say "use Flash more", does that mean using Flash at the beginning of the fight to rack up enmity, or actually use Flash when the aggro is away from you?

I would use flash in steps 1st will blind it 12sec wait for it then again flash >> 6 sec >> 3 sec keep in mind best time to do it is before mountain buster it can miss you if time well :P and yes go with VIT FULL till you get gear play about with STR then
Don't go mad at it on a single mob lol

For the most part yes you should be standing still, only time you really need to move is to avoid red aoe. If you use flash after u lost agro, your already off to a bad pull. But yeah if you already lost it on more then 1 mob might aswell spam it. And most go vit until they feel comfy with their gear and hp.