There are way too many that are way too good.
However, there are a set of movies distinguished by the fact that, whenever I see them on TV and decide to watch for a minute or two, I cannot stop watching, regardless that I've seen them a hundred times before.
Here's a few of them, I'm not saying they're brilliant and I'm not saying they're the best... I'm just saying I can't stop watching them:
As Good as it Gets
It's a Wonderful Life
A Shot in the Dark
GlenGarry Glen Ross
There's loads, I'll add a few more...
Jean De Florette
The Magnificent Seven
Treasure of the Sierra Madre
Perhaps you might suggest a few of your own - I bet some of them get added to my list too.
God, I hope none of them are on today, I've got things to do.