Quote Originally Posted by Albions_Angel View Post
The handbook says druids get natures ally as a spontaneous cast. Forgive my ignorance but what does that mean? Is that like a cleric being able to replace any spell with an HP restoring spell? So does it mean that if I learn Entangle, Entangle, Shillelagh/produce flame, I can discard one for a summoning at any time?
That's precisely what it means. You can dump a spell slot to instead cast an SNA of the appropriate level. Per the SRD:
Quote Originally Posted by Druid, Spontaneous Casting
A druid can channel stored spell energy into summoning spells that she hasn’t prepared ahead of time. She can "lose" a prepared spell in order to cast any summon nature’s ally spell of the same level or lower.
(Emphasis added.)

As an aside, the general rule with feats on a Druid is that you only need three:
  • Natural Spell, to use spells while Wild Shaping. It's practically a feat tax.
  • One summon augment spell (such as Greenbound Summoning) to make your summons meatier.
  • One Wild Shape augment spell (such as Frozen Wild Shape for Cryohydra) to make your Wild Shape even more versatile than it already is. And it's pretty darn versatile.

As for that spell recall thing, a quick search turned up several options:
  • Retrieve Spell (CC): Burn TU uses to recall a spell. Only works for spells derived from classes that use TU.
  • Chaotic Spell Recall (FCI): 1/day recall one spell with the [Chaotic] descriptor you've already cast. Swift action. Requires Abyssal Heritor feats.
  • Call of the Undying (RoE): 1/day recall one spell you've already cast. Swift action. Requires Elf, Aerenal region, access to Deathless domain.
Don't think any of those work for you, unless you plan to play an Aerenal Elf and can gain the Deathless domain as a Druid.

But since I've mentioned RoE, and you say you're good with Races books, are you set on a Dragonborn Mongrelfolk? If not, consider the Shifter, also from RoE. It has two really good racial substitution levels in Druid (the third one is rubbish). And if you plan to indulge in some minionmancy, there are few Druid PrCs better for the task than Moonspeaker.