Drain salmon, reserving liquid; add water to salmon liquid to yield 1/2 cup. Combine salmon liquid and gelatin in a small saucepan; cook over medium heat, stirring constantly, until gelatin dissolves. Remove from heat, and set aside.
Remove skin and bones from salmon, and discard; flake salmon.
Place gelatin mixture, salmon, onion, mayonnaise, sour cream, lemon juice, garlic salt, dill weed, pepper, and parsley in container of an electric blender; process until smooth. Pour mixture into a lightly oiled 5-cup fish mold. Chill until firm.
Unmold onto a serving tray. Garnish with aspic, cooked pasta, and green onion strips; sprinkle with paprika as desired. Serve with assorted crackers.
Note: Recipe may also be prepared in a food processor. Position knife blade in processor bowl; add ingredients. Process until smooth, and proceed as directed.