I've stayed at Ottawa Lake campground a few times now. Every time I've been here, I've been pleasantly surprised by how well the grounds are maintained despite having relatively high traffic. In addition to having restrooms and showers, they also have laundry facilities. And, they do sell ice cream and marshmallows at the park office.
During warm summer days, you'll find the beach packed with people. At sunset, however, you just might have that beach all to yourself. While there are few trails in the park, you can walk across ZZ to Scuppernong Nature Trail. Or, hop in the car and drive over to Scuppernong Trails, Brady's Rocks, or Paradise Springs.
As for my campsite, I recently stayed in site 377. This site offers a peek-a-boo view of the lake. I was also delighted to find a trail running from the back of the campsite and along the lake. While I was there, I experienced heavy rain for much of the night. I'm happy to report that this site is on high ground with decent drainage. So, no flooding to speak of.
You'll notice I'm giving 4 stars instead of 5 for this campground. This is primarily due to noise. On the upside, you'll hear a symphony of crickets at night. On the downside, you'll also hear road noise, slamming car doors, and those few folks who are just a little too loud after dark.