Last year I did Christmas Eve dinner at Napa Rose. They had some special Christmas themed courses as options in the tasting menu. I enjoyed it, it felt very festive.
The holiday season at Disneyland Resort offers extensive décor all around both parks, all 3 hotels and in Downtown Disney. Almost every restaurant and shop has some sort of Christmas tree (often themed to the location) or garland/wreaths, or, in the case of the restaurants at the Grand Californian Hotel, gingerbread houses.
In this post - http://www.disboards.com/threads/di...iting-details-for-2015.3358217/#post-52730328 - look for the "Christmas Eve and Christmas Day Dining Information" heading. Go to the 2013 category (2013, not 2014) and click on those 2 links for ideas of many/most of the places around DLR that will be offering special meals. Even though some of the dishes may vary slightly in 2015 and the prices will have changed, chances are the same restaurants will be offering special meals once again.