Coat a Dutch oven with cooking spray. Add meat, onion, and green pepper; cook over medium heat until meat is browned, stirring until it crumbles. Drain mixture, and pat dry with paper towels. Wipe drippings from Dutch oven with a paper towel.
Return meat mixture to Dutch oven. Add chili powder and next 12 ingredients. Bring to a boil; cover, reduce heat, and simmer 1 hour or until mixture is very thick, stirring often. Remove and discard bay leaf.
To serve, place 3/4 cup spaghetti on each of 6 plates; spoon 3/4 cup chili over each serving. Top chili evenly with cheese. Add oyster crackers, if desired.