1) As a guideline, thinner, fast cooking foods over a direct heat are cooked with the lid open. This allows you to attend to the items that will cook in a short amount of time and monitor their progress so they don't burn. If you're giving them a quarter turn for a nice set of grill marks then you'll be moving them a lot anyway and won't need to close the lid.
1a) However, if you're trying to impart smoke flavoring in the food items you'll probably want to shut the lid. You'll also be cooking over a lower temperature fire and won't have to move or turn the food as often. Thicker meats, like Jamaican Jerk Pork, are cooked with the lid down on a lower heat and can stay on the grill 40 to 60 minutes. To control flare-up’s you can close the lid or sprits with water. It’s all a matter of technique for what works best with what you’re cooking. You may want to cook in two rounds, half with the lid open and half with it close to see which works best for you. Try it with burgers, chicken, steak or fish and see if you notice a difference then decide if you should cook with the lid open or closed.
2) Sounds like the heat was too high for those ribs. They will cook faster on a grill than a smoker, but shouldn’t be burnt or dry. Next time try a lower gentler heat. Did you have a drip pan under them? And did you have a pan of water in your grill? These two items will help yield better results. Yes, You should turn the ribs on a grill before basting. Turning is not necessary on smoker though. How was the flavor? We’ve had a lot of discussion on ribs in the past so if you’ll do a search on the board you will find more information that will help.
Good luck on the next batch. They’ll get better each time you cook them and soon you’ll be dazzling folks taste buds!