Pour water to a depth of 1 1/2 inches into a 3 1/2-qt. saucepan; bring to a boil over medium-high heat. Reduce heat to medium, and simmer. Whisk together eggs and sugar in a 2 1/2-qt. glass bowl. Place bowl over simmering water, and cook, whisking constantly, 5 to 6 minutes or until mixture becomes slightly thick and sugar dissolves. Remove from heat.
Place gelatin in a small bowl, and gradually add 1/4 cup boiling water, whisking constantly until gelatin is completely dissolved.
Beat egg mixture at high speed with a handheld electric mixer 8 to 10 minutes or until ribbons form on surface of mixture when beater is lifted. Add gelatin mixture, and beat 1 minute. Fold in peach preserves and salt.
Beat heavy cream in a medium bowl at medium-high speed 2 to 3 minutes or until soft peaks form. Fold one-third of whipped cream into egg-and-preserves mixture; gently fold in remaining whipped cream.
Spoon filling into baked crust; arrange peach slices over filling. Cover with plastic wrap, and freeze 2 hours. Dollop with Sweetened Whipped Cream just before serving.
Tip: When beating the egg mixture, stop the mixer occasionally, and lift the beater. If drips form ribbons that hold shape for 1 to 2 seconds on surface of mixture, you're ready to add the gelatin.