INT 14 is enough to take Wizard levels. Remember, you need to have 10+X INT to cast a spell of level X. Example: If you want to cast a level 7 spell, you need at least INT=17. So if you choose INT from now on (or even Greater Intelligence as (Bonus Wizard) Feats) you'll be safe.
You can already frontline pretty well, I assume. Are you DEX or STR based?
-STR, then you could go Steelcaster: wear a Full Plate and take the Still Spell feat. You can cast spells 1 spell slot higher (yes, this is a decent advantage, especially since you won't gain caster levels that fast) without Arcane Spell Failure. Automatic Stil Spell I+II+III will be out of reach, since you need to be able to cast level 9 spells.
Conclusion: if you value AC above casting higher level spells, go for this way. I wouldn't do it, since the effect of your mage levels will be even less visible then.
-The other option would be to go with some clothing (no or very low AC) so you don't have any Arcane Spell Failure. Great for DEX builds also. This would be my pick. You can still use a shield, just unequip it before you cast, then equip. I do that and don't mind.
Mages have some good buff spells on the lower levels for if you want to solo, like Mage Armour, Protection from Evil, Keen Edge, Shield, Flame Weapon, Greater Magical Weapon (although this will be only a good spell on higher levels), Bull's Strength, Cat's Grace, etc. to name a few. Problem: short duration. If you don't mind buying Rods to Extend the spells, it's not that bad. Otherwise, be sure you take every opportunity to rest once the 16 RL minutes are passed.
Another question would be: chose a specific school or go general. Since you know 0 about mages, I would normally recommand general. But in this case a specific school would be a good choice: you'll have 1 more spellslot for ever level of spell. The drawback is that you can't cast spells of the opposite school, so you'll need to look at the spells of those schools a bit and decide which ones you can do without. If that's too much work, just go general, that's never a bad choice.
All in all, it's not a bad move. Just don't expect too much greatness from your spells at the lower levels, but the buffs are decent at least. I think it will be fun if you have a few mage levels under your belt.
If you have questions, you know where to find me
