Theme development

I'm sitting here trying to convert a design at a old page to a Drupal theme. I took adc theme and started to convert, but I just don't get it right. I don't know that things to remove that I'm not going to use.

Page that I'm converting from:
Page converting to:

The old page uses tables and that is the thing I only been woking with. A page with only div tags is like a small hell for me. The thing I need is a reference design locking like the old page that I'm converting from. The aesthetic things can I fix for my self.

I'm a total CSS newb and I'm wondering if anyone has a good source for a "cheat sheet" style chart for CSS syntax? Something that shows all available options per command.

i.e. for the text-decoration:

h1 {text-decoration: overline}
h2 {text-decoration: line-through}
h3 {text-decoration: underline}

Thanks in advance.

I was wondering if anyone might be able to clear up the differences between a template, a theme, and a skin.

I'm also wondering how css fits into these and what needs to be edited and when.

Any experiences and examples are certainly welcome.

Thanks very much.

I'm encountering an interesting bug in IE6 on my web site, where the background colour for the first block / node on a page doesn't get implemented. If you visit my site http://dash.yi.org and look at the files page for example, you will see what I mean.

I'm using the ADC theme, but I'm lost as to what I can change to fix this. Obviously, the true answer is to use Mozilla, where it renders perfectly. But I'm a perfectionist ;) any ideas?

After discarding the interlaced theme because of lack of support for adding header links and my own limited knowledge, i'm in the task of making my own template this time using the xtemplate.

After making several changes in the css i see that all my changes related to text and graphics work as intended but the backgrounds are not showing in Mozilla 0.9.1 or IE 6.0.28.
The strange part is that if i use the WebDeveloper Plug-in of Firefox and click the Edit CSS then the backgrounds appear. ?:(

There exists a php drupal function to know which user is visiting a page?

thanks