There are several that I would call favorites and watch every time they're on--and would even consider shelling out money for the DVDs. Flip That Romance, Falling for You, Royal Matchmaker, Love, Romance and Chocolate, Love to the Rescue, Cooking With Love, Pearl in Paradise, Paris, Wine and Romance, Winter Love Story (okay, sorry, that's way more than five). As @TVFan17 says, I'm not even going to get into the older ones, because if I did it would be the world's longest post.
Except to say that speaking of Hallmark Hall of Fame, my all-time favorite HHoF movie was The Love Letter, with Campbell Scott and Jennifer Jason Leigh. Oh, how I love that movie.
ETA: I only lasted half an hour with Christmas Camp. The lead actress grates on my nerves, and it just seems so...cheesy. Not sure if I'll try it again at Christmas time.