There are times when you want to add a bit more fun to your dinner party, and one way to do that is build around a theme. Having a theme will also make everything from choosing the menu to picking the table decorations easier. I have some suggestions below that we have found successful. Try one of them, or maybe they will inspire you to try a theme of your own.
1) Pick an upcoming holiday as the theme to build your evening around. For example, a menu featuring Mexican food can be part of a Cinco de Mayo party. Margaritas can be served, and the music can be mariachi flavored.
2) Seafood Dinner Sometimes we were in the mood for seafood and built our dinner party around that. Our Seashell silverware sets were one more way to set the tone for a wonderful evening.
3) Have a bite sized meal. This can be great fun for a very casual dinner party, one where the guests might stand and mingle throughout the evening. During the evening serve a medley of bite sized foods. Start with traditional appetizers and move on to bite sized portions of more main course type foods. And of course finish with various small desserts.
4) A progressive party can be a tremendous amount of fun. While there are any number of ways to do this, we joined with 5 couples on our street and went from house to house. At the first couple's house, we started off with a glass of wine, and then went from house to house for a 4 course dinner. (Two couples combined on the main course to make the work required more equitable.) This ended up being an absolutely magical party as going to each new house injected excitement into the group, keeping the energy levels high all evening.
5) Game night is a very common theme for a party. We have a number of friends who enjoy playing cards so that is what we most often choose. Again, these are very casual affairs, with a very simple menu. Dessert is usually served as kind of an intermission during the card game.
6) Pizza party. I would make the dough for a number of small pizzas. Then we would lay out any number of topping and let the guests make their own pizzas. This is a very casual dinner, and we often would do this or something similar if our guests didn't all know each other. The interactions around the cooking area were a great way for new people to meet.
7) Garden party. Just sitting outside is a great way to make a dinner party feel special. Of course the weather might have something to say about that, so do have a backup plan ready......
8) First night of winter When we lived in ski country, the first day of snow was cause for great celebration. The next weekend my sister would host a dinner party where white was the theme. The guests were expected to all be dressed in white, the decorations around the house were snow themed, and the food was white (think fish, cauliflower, mashed potatoes, etc.) and only white wine was served. The food may not have been the best ever, but these were always fun evenings as we all celebrated the start of another ski season.