First of all if you are interested in Spanish and Christmas there is a list of vocabulary here which may help you to understand some of the things going on in Spain at this time of year.http://lingolex.com/christmas.htm
Unfortunately the 24th of December is possibly the worst night of the whole year for going to a Spanish restaurant.
Spanish people eat together with their family on the evening of the 24th Dec.
Therefore almost all restaurants are closed.
You may find some Morrocan restaurants open but even they may close.
Here is a Morrocan (they don't serve alcohol here) http://granadainfo.com/arrayanes/index.htm
Chinese restaurants are probably open.
A good chinese restaurant is the Leoneshttp://granadamap.com/leones_chino/
Make sure that you have bought enough food so that if you can't find
anything open at least you can eat.
Everything will be very quiet in the street between about 8pm and 12
pm on the 24th.
The 25th is different you will find most restaurants open.
To be really Spanish have a look at some of the Belens (bethlehem scenes)
Try some Spanish sweets such as polvorones mantecados and turron
Granadainfo have a page about San Luis apartments where Adelfa is located.
If you click here it will show you all places with 1000 metres of your accommodationhttp://granadainfo.com/luis/nearest_places.php