Longest distance ever traveled? - At one time was probably the flight between Newark and Narita (Japan).
Farthest North? - St. Petersburg, Russia
Farthest South? - Puerto Vallarta, Mexico
Farthest East? - Moscow, Russia
Farthest West? - Seoul, Korea
Highest Mountain: No idea. On a family vacation as a kid I recall seeing a sign that said we were above 12,000 ft in Colorado somewhere.
Hottest Temp: Outdoor temperature was probably between 100-110.
Coldest temp: Not sure. In Korea I wore every single piece of cold weather gear the army issued at that time. I was in Moscow from late April to Halloween, so I didn't get the full winter there. I only visited St. Petersburg in the summer, including the "white nights" of the summer solstice.