We've stayed at both and love them for different reasons. POP is such a happy place it seems to keep you going, full of energy. POFQ is relaxing and laid back. The rooms are so close in size that it's hard to say there is much difference. With children as little as yours, if they are using the sink, you will be picking them up to reach anyway, so having two may not matter. I stayed at POFQ for the first time when DD was 2 and DS was 3. They are now 16 and 17(well, 18 in four days).
Our most recent trips (in the last two months) were to ASMusic (awesome for teenagers!!) and POR. ASMusic has the same feel as POP--a feeling of Disney and excitement. POR is very relaxing, even more than POFQ. Having the river run through the resorts, and right outside our room in Parterre Place, was awesome! We were close to everything and the boat ride was wonderful!! DH says that POR is the best resort at WDW! We've stayed at almost all of them, including the deluxes, so that is a big statement.
No matter where you stay, you will love it!! They all still have the Disney feel, but the values just have a little extra touch of the fun side of Disney.