Actually, none of the above. Try using 3M SMR, and then a glaze like mentioned below, and then seal with wax. In my experience, SMR has a huge amount of fillers, and is really good at covering up light scratches and swirls. Unfortunately, it'll only last a wash or two.
Nah, it's like any glaze or filler type stuff. It looks really good when you're done, but then you'll start to see it again in a couple of washes. IMO, you're better off getting rid of the worst ones before you attempt to fill and cover up the rest, then it's not as noticeable.