For most people and languages, the difference is lol(x, y) vs. x.lol(y), which makes OO absurd (and operations tend to suck more on x.lol(y) notation, like string1.equals(string2), ugh). Then you have inheritance, which means you get a free dish of spaghetti code. It's just dynamically updated copypasta, and come to think of it, spaghetti is pasta.
That's ALL there's to OO; note that garbage collection, exceptions (= goto 2.0), function and operator overloading, etc. are not OO features, and many languages offer them procedurally.
If you are serious about OO, then OO is about functional units responsible for keeping their own state, and can provide a good abstraction. Inheritance and mixins can have their uses as well, but for this to be comfortable, you have to work with a dynamic language such as... I'm not going to give examples because I'll be called fanboy.
Of course, and like with pure anything, pure OO sucks. Not all structures, models and algorithms adjust to OO well. Pure OO languages which shove OO up your ass all the time, like Java, are bound to suck. (Java is bound to suck for many other reasons as well.) So you use OO when it fits, procedural programming when it fits, and functional programming when it fits, and finish early.