A great RV spot in Fruita is James Robb:
Campground Details - JAMES M. ROBB-COLORADO RIVER STATE PARK - FRUITA SECTION, CO - ReserveAmerica
Right beside the Colorado River, and easy access to the town, it has large pull throughs as well as back ins. Well kept, spacious, and friendly staff.
As far as trails go, can't help much, but the Robb Park is a central location. Turn right toward the Colorado National Monument when you leave the RV park, then another right when you cross the river, and it takes you out to the McInnis Canyons park, with access to lots of trails.
Here's a few links that may help you:
Trail Map PDFs - COPMOBA
The Skid Map
(click on the map to get closer, then the trails are highlighted).
Hope that helps! I'm envious...one of our favorite places. I grew up in Grand Junction.
Joe and Debbie, Emma the Aussie Cattle Dog who adopted us
2012 Discovery 36J, Blue Ox and Air Force One, 2010 GMC Acadia Toad
USAF (Ret) WDØM http://wd0m.com