If you are looking for an old barn Stormer can't go far wrong with a Steve Collin's Eubank or if you want something a bit more recent a canelo GGG maybe then there is always something like Calzaghe Hopkins
My experience is that anything black and white is going to be a big turnoff for some people. Even though I also recommended some of these, it occurs to me now that even non-HD color may be alienating.
That's actually the best idea. If you show casuals good/legendary fights they might feel let down for the main event.
People have short attention spans especially if they're not into boxing to begin with... I recommend shorter fights that have incredibly high levels of skill and violent outcomes: Pacquiao-Roidquez 4 Pacquiao-Hatton Donaire-Montiel Martinez-Williams 2 Hagler-Hearns
Morales v Barrera trilogy Salido v Lopez 1/2 Vazquez v Marquez trilogy Marquez v katsidis Gatti v Ward 1 Fury v wilder 2
Pac gave Mosley a glove tap after he knocked him down. Pac gave Rios a glove tap after he smashed him with a crazy straight left. Pac started visibly pulling his punches against Margarito in the late rounds. This does not seem like a guy who would roid/do anything to win. Plus he has hurt/dropped every single opponent in his VADA-tested fights.