I told my mom last night if the comet hit it would hit water or Russia.
What comet? The approaching body is a near-Earth asteroid made of stony material. It orbits close enough to the Sun that any ice would've long since evaporated away. Comets come from further out in the Solar system, past the "snow line."
And of course by last night we had 2012 DA14's orbit calculated precisely enough to know there was zero chance of it hitting the Earth. Something would've had to push it rather suddenly off course in order to make that happen.
Otherwise, as a rule, there's some merit to your observation. More than 3/4 of the Earth's surface is water, so the odds are heavily in favor of asteroids impacting or exploding over water. But the odds of an impact over Russia aren't quite as great. Certainly it's got a larger area than any other single
country, but it's only a bit over 1/9 the total land area of the planet, so the odds overall are in favor of a land impact somewhere other than Russia.