For the 1968 - I believe that's a Late-Die State die. Meaning... the die had been used for many, many, many punches and the metal slowly flowed from the repeated strikes. It begins to look... melty. Just like your coin. In other words, your coin might have been one of the last ones struck with that particular die. Cool!
As for the 2000 - funky! Wish I could tell you!