I agree that it depends on how you like to travel. I don't think concierge is worth it at DL. I haven't gone that route but I have looked into it and to me, its not that big of a deal and very overpriced.
Paradise Pier is a really nice hotel. I love the oversized rooms, you get free internet access, a sofa that makes into a bed (other places you'll have to rent a rollaway which adds up), free parking and Disney customer service. I like to book a theme park view when I stay at that hotel, to me that is worth it!
If you stay offsite, you'll have a wonderful time, save a ton of money and be just fine. I think the Hojo is very nice, it has some nice grounds and the pirate splash area would be a big hit with your 2 and 8 year old and I am sure the 13 year old would have fun too! The rooms are nice sized and distance wise its about the same walk as the Paradise Pier is. And as Linda said, the CCI is another place to consider, it gets rave reviews and the free breakfast there sounds very nice. I rarely hear a bad thing about that place. Then of course you can go for convenience and stay at the crosswalk at Desert Inn as you did before or one of the other places right there at the crosswalk.
I think you just have to sit down and look at the budget, what you want out of the trip etc. You can't make a bad choice! But if you want extra special, staying onsite is awfully nice. One big perk is that as an onsite guest, you will be eligible for Magic Mornings each day they are offered vs. the one day your park hopper ticket gets you. That extra hour each morning to do Fantasyland and some of Tomorrowland is really nice. Not something that makes or breaks the trip, but a nice perk.
Here is a thread going right now with some nice pictures of the PP Hotel:
http://www.disboards.com/showthread.php?t=2050258