What a cool story...and neat family history! Here's my $.02 = the value of the packs is best determined if you know the players inside. However, if the cards inside are damaged in any way, even minor damage, selling the cards as unopened packs would probably bring you more money. Weather damage, like years of uncontrolled storage that is too cold, too hot, too dry or too humid, will cause significant damage to cards. If this is the case, or even a possibility, there is no doubt unopened packs will yield you more $ than opening a pack and trying to sell a bunch of damaged common cards at $.50 each. You could try and auction a few on ebay and see what they bring as packs to tes the waters.
I would be willing to make you an offer for the entire set, or a portion, if you are interested in selling any. My son and I have collected cards for years, but we do not have many of the "oldies but goodies". We would be willing to take the risk. They would be appreciated and cherished by our family for generations, and bring back many memories. Email me if this interests you. Regardless, good luck and have fun!