It's quite difficult to find good ranch sauce at the grocery store. The closest I've found is Marie's, and it's not ideal. I love ranch on everything though...pizza, steak, chicken, fries. Ranch on honey bbq boneless is heavenly. Prefer honey mustard on fries, but again you have to get it at a restaurant. They just don't have the right kind at the grocery store. And sometimes even the restaurants screw it up...many times way too mustardy or strange tasting. There's a local irish pub here that has just about the best HM I've ever tasted. Okay, I guess I'm a sauce freak.
My favorite fries are applebees, there's a bit of seasoning on them, and the HM is good. I like arby's curly fries, and chikfila waffle fries. I dislike steak fries, and strongly dislike from the freezer fries.
I'm not really familiar with vinegar on fries, haven't seen anyone do that. Poutin is great though.