Yes, but an ending comes from the whole product. You can't compare the endings of entirely different games because they're entirely different games with different stories and goals. An ending is only as good as the goal it's trying to achieve.
Yes, because I feel different senses of accomplishment. Mass Effect 3, you feel achieved (or rather were supposed to, if you didn't like the ending) because you finished your life as Commander Shepard. Which is the EXACT polar opposite of Super Mario Bros which makes you feel achieved because you survived (or rather survived the war of attrition) and saved the princess.
Doesn't matter. You made a new person move with the poll sir

Experience teaches. I can watch people speak a different language all day, doesn't mean I'm going to pick it up.
Thank you.