Unfortunately, the RPR is far away from the parking garage and restaurants on Kirkman road. If you were two adults and wanted to go for a half hour walk, then I'd say yes, go for it. But with a 5 and 7 year old, no. The parking garage is located next to the PBH and across from the HRH, so those people can walk, it would take them about 15 minutes, and there is a stop light to stop the cars. But from the RPR, you'd have to add the 15 minutes of walking from the hotel, to city walk. The kids will be tired out walking that far.
People staying at the RPR can walk across the bridge on Universal Blvd to Wet N' Wild, and there is a restaurant across the street from it, which would take about 20 minutes. Otherwise, there is nothing near the RPR. Your view out the windows will be of the parks, or the highway.
Your best bet, is to ask the limo driver to stop at Publix grocery store before arriving to the RPR, get a styrophone cooler in the beer isle, milk, juices, doughnuts, and plenty of booze. Most limo services will stop at Publix as a perk for using them.