I'll give you a few (before he even won a title):
In 1988, Michael Jordan averaged 32.5 points per game (Higher than any of the seasons Lebron has played in the NBA),
8 assist per game (more than Lebron has ever averaged in a single season),
8 rebounds per game (more than Lebron has ever averaged in his previous 9 seasons)
2.9 steals per game (also more than Lebron has ever averaged in steals),
on 53.8% from the field (Though Lebron currently sits at 55.5 - Jordan's 53.8% is still higher than Lebron's previous 9 seasons). Not to mention Jordan's 85% free throwing shooting compared to Lebron's 73%.
That was an epic season done out of necessity, due to the fact that Horace Grant and Scottie Pippen had not yet come of age. Lebron doesn't have a season better than that, and that arguably isn't even Jordan's best season. With the aforementioned facts I've just supplied; it's safe to say, from a numerical perspective, Michael Jordan could do everything Lebron can do - at a higher rate within a 48 minute span. Thus making Jordan, presumably, the better basketball player.
Also, the year before...MJ won a Scoring title and a Defensive Player of the Year award in the same season. Making him not only the best offensive player in the game, but the best defensive player as well...has Lebron ever done that?
I won't touch Lebron's well-documented coronary issues.