Any weight, any time and any generation before or during your own. Mine would be 1985 Marvin Hagler vs Thomas Hearns. Simply due to the excitement and pure heart of both fighters slugging it out from round 1 and giving it their all! Its like watching two Bambi's move around with the power of the hulk hitting granite off their chins. Ending with a great KO by Hagler. And lastly I would choose 1927 Gene Tunney vs Jack Dempsey. Ive always been fascinated with the golden age of boxing in America and the stories and ferocity of Jack Dempsey (Something missing from todays HWs) The decision for Tunney is something I would have loved to have witnessed because fighters in those days never seemed to follow the hit and not get hit mentality that most fighters carry and believe In today. At least not in the 1920s for HW anyway.
Charles vs Moore 1, 2&3 Edit: I know you said two, but I couldn't decide which of the two I wanted to watch. The 1st is said to be a virtual shut out from Charles. The best at his best type of performance. Whereas the 2nd is closely fought tactical fight between two top 10 ATGs. The third is said to be one of the most electrifying fights of all time. Either way, none are on film, and I want to see them.
Joe Jeannette vs. Sam McVea. Any Harry Greb fight, though if I had to decide I would say the first Tunney fight.
I won't say Rumble in the Jungle, though I'd have liked to be there, seen the concert etc. So I'll go with: (1) Bowe-Holyfield [either I for the fight or II for 'fan man']. (2) Robinson-LaMotta II.
cotto vs margarito donaire-inue mosley vs de la hoya gatti-vs ward morales vs barrera tyson vs holyfield
That's really tough. Out of pure reflex and right off the top of my head; LaMotta-Robinson II Larkin-Graham
Tyson vs Berbick Hearns vs SRL 2 Koopmans vs Blanchard Holmes vs Witherspoon Witherspoon vs Frank Bruno Honeyghan vs Don Curry