Pumpkin Nights is a seasonal attraction here in Salt Lake City that offers a family-friendly Halloween experience. There are semi-scary bits including an optional (mini) haunted house and some spooky sound effects but the 6 year old, 4 year old, and 11 month old made it through with no complaints or tears. My only caution would be this - bring warm clothes because it's mostly outdoors and our light jackets didn't cut it at the end!
The attraction offers more than 4000 pumpkins, a series of themed areas, on-site pumpkin carving artists, movie screenings, face painting, a game area, and other random bits of family fun. The highlight of the night for our kids was the digging area where they were allowed to dig up and keep a small pumpkin. There's also food and alcohol on site and costumes are encouraged. Check out their website for more information.