The Dungeon Adventure Path is pretty OK, I think, but not as good as they want you to believe. Actually, most parts of the series are nothing more than extensive dungeon crawls with exotic critters taken from non-core books like MM II oder Fiend Folio. While this is fine in itself, it could get boring after a while.
So, while the AP is slightly overrated, there are still some gems to be found. I especially like Foundations of Flame, which plays out like a catastrophe movie scenario.
For a new group, try Death in Freeport, Of Sound Mind or Sunless Citadel.