Serve iceberg lettuce wedges instead of torn salad greens to save time making a salad. Also, before refrigerating iceberg lettuce, wash and remove the core so each time you need some for salad it's clean and ready.
You can also prolong the life of your lettuce fresh by wrapping it in a paper towel, and then putting it in a sealed baggie in the fridge. This keeps the air out and the excessive moisture off of the lettuce at the same time.