We generally stay onsite as well, in 13 trips we've only stayed offsite totally (sometimes we do a split stay with a couple of days offsite then switch to onsite for five or more nights) three times. Here are the places this onsite lover recommends!
Hojo. Your toddler would probably love the new splash zone. The rooms are large sized, the grounds very pretty and you have Mimi's and McDonald's right nearby for easy meals. Mimi's does takeout which is very nice. The Hojo employees are all very nice. The walk is about the same as the walk to the DLH, but it seems longer. As opposed to going up DTD, you are on a busy street. Some of the hojo rooms face the highway, so make sure you pay for a room not on that side. I know a hojo regular can point you in the right direction to accomplish that. And the great discounts make it very cost efficient.
Best Wester Park Place Inn: This is the closest hotel there is. Its nice and clean, its not fancy and there are no grounds. But its at the crosswalk and so nice at the end of a long day! It also comes with a free contiental breakfast to save you even more money. Our room was spotless and every bit as nice as our Hojo room but for a longer stay or if you want much in the way of a pool scene, the hojo is nice. The BWPPI has a small pool that is very lackluster!
Tropicana: This is right next door to the BWPPI so also very close. It also has a free breakfast. Our room was very nice, extremely clean and while it has no grounds, it does have some pretty landscaping touches (potted flowers and plants, palm trees) and a very nice pool area (small pool, large spa but no baby pool). It has much less of a parking lot feel and a bigger parking lot than the BWPPI. I really liked this one probably the best. Simply for the location and the fact that it had a nice pool area my kids loved.
I picked BWPPI for our next trip because I have two teens (boy and girl) and the BWPPI has very reasonable mini suites that give us a sofa bed. That is the only reason I go there over the Tropicana I might add, those mini suites!
I'll also chime in that the Candy Cane looks nice. I just can't find a room there big enough for us now that my kids are older. But it looks very charming, they have a much nicer breakfast than the places on Harbor and it has its own, dedicated shuttle. Its about the same distance to the gates as DLH and Hojo, but that shuttle would be nice to have. Its generally pricier than the ones right across the street.
I always start out looking on Expedia and then check with the direct hotel sites. For my upcoming stay, Expedia was $10 a night cheaper than going directly through Best Western. But of course I had to pay up front. The Candy Cane doesn't have any rooms available through Hot Wire or Expedia. You have to book with them direct and they do have AAA rates.