[Bozos of Bones]

Chain Lightning is broken, as it only jumps to two targets. Lightning Bolt is dangerous to use. Ball Lighning is too high level for it's use, too constrictive. Destruction can really really help, and is a definite pick for tough fights with some powerfull enemies. Tremor can be usefull if aimed carefully, but it's level is IMHO too high for it's damage. Acid Storm is great, really usefull! And Fire Storm is one of the best fire spells in the game, given it's level and damage potential. Now, something about Static Charge and Call Lightning. These spells, if cast one or two, won't make much difference, as their damage is spread over many rounds, and in most cases the battle lasts through only 2-3 of these. But, it's main asset, is the ability to cast it before battles, as a buff. All you have to do then is wade in a bunch of enemies, and watch the thunderstorm! Battle is over in a turn, maximum!
Now, on the other side, we have Marty's suggestions of Flame Strike, which rules, Fire Storm, which also rules, Meteor Swarm, which is a judgement day spell, and Sunscorch. Sunscorch is not a praticularly powerfull spell, whe compared, but it's biggest asset is that some races and classes may cast it as a special ability. When the battle begins, all the party members throw down Sunscorch at the strongest enemy, and he stands no more. IMHO, IWD2 has much too many fire spells, and the alternatives are either underpowered, broken or non-existant(no level 9 lightning or acit or cold spell anyone?).