Per the above points:
-I've only seen the first 'How to Train Your Dragon', but I definitely reccomend it. It's an excellent film, and actually my #1 DreamWorks film.
-It's not in the style of Prince of Egypt - it's certainly DW's most 'serious' franchise post-PoE, but it's a completely different tone, being focused on action-adventure. So if you liked PoE, it's not a guarantee in of itself that you'll like this.
-Post Shrek 2, of the DW films I've seen, I'd still maintain that Over the Hedge and Kung Fu Panda (the first) are good movies. But in hindsight, I think it's the first Shrek that really gave DW its 'voice,' so to speak, in that it defined what we expect from a DW film (focus on humour).
-Concerning 2D animation, DW seems to be in the same place that Disney is - 2D animation for cartoon series? Fine. 2D animation for films? Nup. I don't particuarly mind, but don't expect to ever see a DW 2D animated movie again.
-Surprised that they're definitively declaring it to be the final installment. We'll see how long that lasts...