In small saucepan combine sugar, vinegar, salt, and ginger. Stir over medium heat until sugar dissolves. Remove from heat. Place in a medium bowl. Slowly add both oils to sugar mixture in a thin steady stream, whisking constantly until thickened. Stir in sesame seeds, sesame oil, and cayenne pepper; set aside.
In large bowl combine melon and cucumber. Add 1/2 cup of the dressing; toss to coat. Line salad bowls or a platter with lettuce; top with melon mixture. If desired, sprinkle with cilantro and bacon. Pass remaining dressing. Makes 6 servings.