Toss shrimp with salt. Heat one tablespoon oil on a grill pan or skillet over medium high heat. Add shrimp in a single layer; do not crowd. Cook about 2 minutes. Turn and cook through about another 2 minutes. Remove from skillet.
Combine shallots, sherry vinegar, mustard and pepper in a small bowl. Whisk in olive oil.
Toss together basil leaves, lettuces, peach, feta and shrimp. Pour dressing over top and toss to coat.