This might be a no-brainer to some, but I wanted to include it, seeing as how it's a family favorite and all...
Classic Orange Jello Salad
1 small pkg orange jello
1 cup boiling water
1 cup orange juice
1 can mandarin oranges, drained
Mix the boiling water into jello powder, until dissolved (approximately 2 minutes).
Stir in orange juice.
Pour in mandarin oranges and stir to spread evenly through liquid.
Chill at least 4 hours until set.