New spells - any of them decent ?
 

I've already completed one play through (warrior impossible) and am some portion of the way through my second (mage impossible). Historically fire rain, time back, trap and phantom were the spells of choice (among others). Now there is an entire new spell class (though some of the spells in that class are not new). Anyways are there new fav spells ?

Blizzard rules for direct damage, Sonic Boom isn't bad...
Winter Dance can be nice early on, and Magic Missile as well...

Blizzard is probably the best direct damage spell in your arsenal. A bit costly but it is devastating to demons and yes dragons. Gift is somewhat useful and as mentioned, Winter dance and magic missile is nice early on.

Is Hel's messenger Rune magic? Either way it is really good mid and end game

As a mage, which school should I be maxing and/or spells should I be looking for early on to help with the Spider Boss? I have higher magic and have 1 pt in each school for the time being.

Pheonix, it's rediculously powerful.
Healing, really cheap and really nice damage early on versus undead also lvl3 cures poison and plague.
Haste lv3 has mass effect.
Slow
Weakness(the one that lowers defence) nice vs black knights and enemies with high defence.
Blizzard it will end up being your number 1 spell
Greasy mist, very nice in combination with pheonix.

I meant more specifically for the spider boss itself what should I look for/spend runes on.

That depends what spells in your spell-book you’ve got, if you have good damaging spells from order like axe or phoenix then go for that. Magic missile in rune school or flaming arrow in destruction, bottom line you will need to upgrade the one in which you have some damaging spells, and upgrade these spells goes without saying.

But prior to that you want to get that +3 intellect for having 100 crystals in your bag before you go nuts and memorize all the spells. Destruction spells shine when you give points to increase damage from that school.

Side note: I think you rushed a little to give yourself 1 level in each school of magic (btw what difficulty are you playing?).

Well I'm only playing on Normal so overall I'm not very concerned. I put 1 level in each to allow me to unlock higher magic because I know I wanted that asap. That gave me an increase to my firepower w/out spending crystals which I'm up to 80ish. Been really disappointed that I haven't found a trap spell by level 14, but other than that it seems like people are really ragging on Chaos not getting it done.