Grandpa (me), grandma, daughter, son-in-law, and two small grandchildren will be together for almost two weeks in a two bedroom at OKW. Any suggestions? What should we be sure to do or not to do? Anyone else ever had the courage to do this?

to SeaWorld, which I think is the next best park in the Orlano area. 
) , if you like nature a trip on an airboat ride may be something you'd enjoy but is not practical for the small kids, if you like art the Dali museum in Tampa is VERY much worth the 2 hour drive ( nearer to WDW , Winterpark has a great display of Tiffiny glass). If you find an afternoon that's too cold to swim you can rent a pontoon boat from th marina and pootle through the canals to PO and then onto DTD, it'll take a couple of hours, but it's a nice gentle cruise. If you do get some decent weather, pool hopping is a worthwhile option, we went to Coronado Springs this visit and that does have a great pool,slide and play area.
) so do keep and eye on them lol. She absolutely adored the night parades with all the flashing lights and sparkly costumes. If you visit IOA the kiddies area in Seuss Landing is a magnet for kids of that age, there is water bits for them to play in as well as a number of VERY colourful things to amuse them. They'll probably enjoy AK's play area as well as the festival of the Lion King show, the Pocohontas show, the two bird gardens, petting zoo and ALL the animals there. Character interaction is going to be popular ( but time consuming) it is an opportunity for one set of adults to go off and ride something, while the other set look after the kids in the lines for photo shoots and autographs.