If your overclocking, the E2200 will be easier because of its 11x multiplier vs the E6300 multiplier of 7x. But the E2200 only has 1mb L2 cache vs 2mb on the E6300. If the E2200 can get a good OC over the E6300, that will be your best bet, but the only way to know is like WR2 said, install them both, OC them, and bench them both. Then make your decision.
If your overclocking, the E2200 will be easier because of its 11x multiplier vs the E6300 multiplier of 7x. But the E2200 only has 1mb L2 cache vs 2mb on the E6300. If the E2200 can get a good OC over the E6300, that will be your best bet, but the only way to know is like WR2 said, install them both, OC them, and bench them both. Then make your decision.