Christi,
There are a lot of great evening things to do, from dining, to fireworks, to dueling pianos! here are a few, covering a range of interests, to consider;
BoardWalk
The BoardWalk is a pretty sedate but scenic walking area that is near Epcot and Hollywood Studios. It has entertainment on the walking area, as well asÂ
Jellyrolls for your mom. This dueling piano bar (21 and older) is a fun, festive place!
Downtown Disney
A lot more to do than the BoardWalk, including extensive Disney-themed shopping, Cirque du Soleil's
La Nouba show, and several great restaurant choices.
Theme Parks
Don't underestimate spending some time in the parks at night. They are fun, and you can get a lot more rides in during the later hours when the under-10 set have gone to bed. In particular, your Mom might enjoy the Epcot World Showcase. The restaurants are amazing, covering almost a dozen different cuisines. The shopping brings some interesting foreign goods from around the globe, both pricey and inexpensive.
Send me another question with info on what she likes to do, and what kinds of foods she likes, and I can offer some more specific suggestions.
Have a magical vacation!