The rooms are not huge, you'll be cozy - but the resort has a lot to do. We had two down days from the parks last year, and we weren't bored at POR at all.
There is a good main swimming area with a fun slide that has a little more of a thrill to it than we thought it would! Same section also has a hot tub, a pool bar, and a nice playground.
There's a marina to rent boats and bikes, a good size arcade, a nice lounge that is actually very family friendly and has a GREAT piano player.
There's also a place to rent fishing poles and do some catch and release fishing. The "cruise" to DD is nice and relaxing - and we also took it over to POFQ and spent an afternoon there enjoying the pool at the "sister resort". That pool has what looks like it would be a better slide - very nicely themed - but my family liked the one at POR better. However, we enjoyed the ambiance and the music that was playing at POFQ and it was a nice outing.
POR also has a full-service restaurant that we had a good dinner and breakfast at, though like anything, your experience may vary! The foodcourt was decent and the bakery section was particularly good.
The resort is pleasant to walk around and just "be" at. However, it's not as jumping as some other places you might have stayed...so I guess it depends on what you are looking for. It's not a Boardwalk or a CR, but there's still quite a bit to do if you are looking to spend a day there instead of at the parks, or the 4 yo is taking a nap, but the other two are restless and want to go do something. Plus, the cruise to DD makes it easy to visit there when you run out of options at the resort.
Have a great time!