[CSS HELP] Identifying comments

For a couple of weeks now, i've scratching my head trying to identify the comments divs/class.
I found out it's in albumdesc, but since comments and albumdescriptions two different things, I would like to make my own tag for the comments. But where should I do this? editcaption does not influence what I need.
So, all I need is to make a new comment div/class. But where?

Second: Can I make a new css div/class for mouseover text on a picture? To make a new look of somekind?

Third: How can I make html work in the descriptions field on the front page?

-Andreas.