Actually, don't watch those movies. Here are two gifs that sum up everything you'll ever need from them:
Instead you should watch 7x12 "Time After Time," because it first aired on Friday the 13th of January, and 5x14 "My Bloody Valentine," for obvious reasons!
"Time After Time" is the episode where Sam and Dean prove their ability to synchronize across spans of time longer than their lifespans (even put together!), and that they have the balls to even try. There's a wealth of beautiful Sam and Jody bonding, clotheshorse!Dean, Eliot Ness + awesome 40s!Bobby seamstress lady, Sam and Dean squatting in a vacant house with sleeping bags (!!!!), and Dean receiving bad life advice from someone he admires--which is a favorite thing of mine.
"My Bloody Valentine" is the cannibalism episode, of course. With Unattached Drifter Christmas, an awesome medical examiner/morgue guy, Castiel being the adorable-est Hamburglar, Sam having a demon blood relapse, "Where is the soul of the one who likes cream cakes so much?", people plunging their hands into boiling oil and shoving fries into their mouths as the skin sloughs from their fingers, and Dean being depressed and empty and done with the world. <3