I believe there are a couple of ways to lift your spirits with film. One is to go watch a classic, funny movie. Ferris Bueller's Day Off comes to mind, and I get to call it a classic because it is from the early 80's. I may no longer be a teenager, but I can get into the spirit of a day spent in beautiful Chicago, skipping school, or in my case, I'd be skipping work. Disney's The Kid with Bruce Willis is a good one too.
Or watch a movie that is so engrossing and packed with action and adventure that you forget your disappointments. I like the Bourne Supremacy / The Bourne Identity for a good plot, and white-knuckling, holding-your-breath action.
Another route is to see a foreign film. Reading those subtitles requires more attention. Two of my favorites are Amelie, an inventive mysterious film, and Everybody's Famous! which I haven't seen for a couple of years, but liked it when it came out.
Good luck with finding just the right movie prescription, and let me know how it works out.