Hey, TB! Great idea for a thread.
1. In the tag, you put an = after spoiler and fill in the name or title you'd like to show on the button. It'll only say what you put after the = and will not say "spoiler" anymore.
[spoiler=Name you want shown on the spoiler button]stuff inside spoiler[/spoiler]
2. I think you can do the same with the quote tag. Or alternatively, put author= inside the quote tag, and whatever you'd like to show up above the quote will be there.
quoted stuff
[quote author=author of quote]quoted stuff[/quote]
I hope that helps!