Originally Posted by Drithius
Spellcasting with its feats and counter-spells can be pretty complex in D&D 3.5 (that goes for everything in the ruleset though - the powers that be really went overboard on its new player learning curve). I'd second Dart's recommendation on going with a fighter for at least the Original Campaign until you can get a handle on things.
Still, if you're committed to wizard, your intelligence is your lifeblood; contrastly, charisma for a sorcerer. Not only do you eventually need at least level 19 in your respective stat to cast level 9 spells, but the higher it is, the harder it is for enemies to resist your spells. You'll get a single stat increase every four levels but that doesn't mean your initial stats shouldn't be mulled over carefully. I'd recommend something like 12str/8dex/18int/16con/8cha for a wizard. You could also drop down to 16 starting int for a more balanced character.
-strength: how much damage you do in melee combat; generally how well you manage to hit in melee combat; how much you can carry!
-dexterity: tied to your armor class, provided your worn armor allows the bonus; how well you hit in ranged combat; tied to your reflex save!
-constitution: not to be ignored by anyone especially a wizard who only gets 1-4 hit points per level. For each two points of con, you also gain 1 hit point per level. Retroactive.
-wisdom: for your purposes, simply tied to your will save.
-intelligence: see above. Also determines how many skill points per level you get.
-charisma: for your purposes, will mainly be used to affect charisma-based skills such as appraise and diplomacy. (assuming you don't go sorcerer)
Bear in mind that each of the above stats don't do anything for you in 1 point increments. Associated improvements only happen at even values.
Under your skils as a wizard, you'll want to pay extra attention to spellcraft and concentration.
Lastly, I definitely do NOT recommend a sorcerer for you. Not only will you have fewer spells to experiment with but it will be more difficult to exchange them for other spells in comparison with a wizard.