Classic games had it all: catchy gameplay, excellent music and most of all they were quick to play and didn't take long to beat. Many older titles for consoles, like the Sega Genesis and NES, only take 30 minutes to a few short hours to beat. This means you can squeeze in a quick play session before you go out to eat or get ready for work.
A lot of retro titles are inexpensive, so if you have the means to play one, it's a sound investment. Of course, if you don't have an older console, never fear; many older titles are being remade and rerelased on current platforms.