Dallas has been to the NFL/NFC title game 16 times in 45 seasons, they have won 8. The have a 5-3 record in the Super Bowl won (XXX , XXVIII, XXVII, XXII, VI) and lost (V,X,XIII).
The Packers have been around since 1921, before the NFL.
If the Super Bowl has done one thing it's to educate the American public on Roman numerals.