Hello there! We have stayed at both resorts and they are both great. To answer your question though, I guess you would have to think about what kind of trip you are planning.
If you are looking for a place to just lay your head when you are not at the parks, French Quarter would be best for you. It is compact and convenient. It has only one bus stop and it is very quick to walk through the whole resort.
If however, you are looking for a resort to spend time in, Riverside definitely has more to offer. Our kids are 11 and 8 and really have outgrown the pool and slide at FQ. They do however really enjoy the main pool at RIverside, Old Man Island. Dh and I do too, there are plenty of sunny or shady spots to lounge and actually RELAX!
Riverside also has a nice playground, arcade, fishing hole, horse and carriage rides, Yeehaw Bob shows in the lounge(tonnes of fun!), quiet pools, surrey bikes, marina with watercraft rental, sit down restaurant, and the design your own pasta and salads in the quick service eatery are wonderful!
Of course both have the boat to DTD which is a must do for us for sure!
For us Riverside fits our family better because we like to spend time at the resort, but others love the compact size and convenience of French Quarter.
Whichever you choose I'm sure you will have a great vacation!
Have fun
