This is not even a real debate except for longevity sake as to the goals record. Gretzky had 15 seasons of more than 100 points, including 4 seasons of greater than 200 points.
Ovechkin has the same number (4) of 100 point seasons as Gretzky had 200 point seasons.
Gretzky Highest Point Seasons
1985-86: 215 points (52 goals, 163 assists)
1981-82: 212 points (92 goals, 120 assists)
1984-85: 208 points (135 goals, 73 assists)
1983-84: 205 points (87 goals, 118 assists)
Ovechkin Highest Point Seasons
2007-08: 112 points (65 goals, 47 assists)
2008-09: 110 points (56 goals, 54 assists)
2009-10: 109 points (50 goals, 59 assists)
2005-06: 106 points (52 goals, 54 assists)