TBH it's been a while since I used DOSBOX (never heard of Dropbox) and the compatability issues usually stemmed from setting up GLIDE type games, always got lots of artifacting and display errors.
Dropbox is a file / group sharing website / software, with (very) minor SVN capabilities. It is not an emulator.
I feel the same way sometimes, and find it is due to 2 of 3 issues.
#1. Things (usually slowly) suck more as you get older. This is fact.
#2. Games (, the majority of them,) actually are getting worse with every "generation". You can prove this to yourself by: (a). Missing titles when they come out, and (b). playing new releases before the ones you missed.
#3. So. Much. Filler. Game's nowadays are so much slower, and have so much more combat to the area explored that it can take (I'm looking at you, Dragon Age: Origins) hours to complete one area, without increasing the 'reward' to account for the time spent.