Considering that none of us know anything about your boyfriend (or you), it is really hard for us to give you ideas.
For my boyfriend, we both work very hard and don't have a lot of free time. So for Christmas day, it is our relax and goof off day. We buy a bunch of food and junk food. We buy some fun drinks that we wouldn't normally drink. We get silly cheap toys, games, puzzles. And we pick out some tv shows/movies to watch all day. We do very little but spend time with each other and goof off.
As for gifts, sometimes they are practical (like the time the stove quit working, our christmas present to each other was a new stove) or they are just fun (one year he arranged a weeklong trip for both of us, another year, I got concert tickets for a comic he likes and got a weekend reservation at a high-end hotel).