Maris Otter is a very, very popular base malt. Many brewers use it for all ale styles, American or British. It has a distinctly crackery, biscuity flavor compared to US 2-row.
But US 2-row is a fine base malt for ESB and English styles as well. In fact, you may prefer it because it's neutral; you can make damn near anything you like with US 2-row alone, from Koelsch to IPA to Tripel to Munich Helles.
Pale malt is to a brewer what chicken breast is to a chef. A chicken breast is a chicken breast - bland and unexciting - until you start adding spices or mess about with how it's prepared. The difference between US 2-row and Maris Otter is, IMO, like the difference between chicken breast and turkey breast.* When tasted side by side, with no spicing, the difference is apparent to most palates. When you start messing with them, adding Caribbean jerk or garam masala or ginger and lemongrass, the differences are much less apparent. If you start adding specialty grains to base malts, the differences between the base malts are much less apparent. It's really, really difficult to tell the difference between stouts made with different pale malts, for example; all that roasted-barley character is the flavor equivalent of standing next to an aircraft carrier and trying to see its shape - all you see is grey.
Anyway, I should get off my soapbox and let you get on with your Thanksgiving holiday. Cheers and all that!
* Appropriate analogy, given the holiday, don't you think?.