There are a lot of great places to run in Virginia Beach. The biggest challenge is staying off the busy roads. I like to park at the Convention Center (anyone in the city can direct you there) and run to the Boardwalk when I am in town. There are sidewalks along the streets, and the reward of a couple miles' effort is the beautiful ocean view once I make it to the Boardwalk. There, be careful of the throngs of tourists and occasional bicyclers. You can run as far as you'd like along the Boardwalk before looping around. I also like to run around Ft. Story when I am in town. There is a campground by the beach there that has good shade and nice, dirt-packed nature trails on which one can go as long as the sun doesn't get to you.
There are normally campers and beach-goers out and about, but there will be stretches of path where you will be running alone. I like to run on the beach, too, but only when the tide is out and the sand is packed hard. This is the most fun to do in the early morning or evening when the beaches aren't over-crowded, and a runner isn't jumping over ankles to dodge incoming waves. Basically ANY where you run in Virginia Beach is going to consist of flat and easy terrain. It gets hot in the summer, cold in the winter. Hydrate and dress appropriately.