Unordered lists in two and three columns for posts

Hello everyone. Could someone enlighten me with the following issues:

1. How can I include unordered lists in three columns without using tables? I had already done them via tables (300px width), but I don’t know how to remove the table border from the theme code. The page is here.

I tried using divs and they looked good for two columns. I even managed to get three (two with float: left and one with float: right), but the width part isn’t working as well as the tables and I can’t get them fit at 300px. I left just the tables.

2. On another page, I used two divs and wanted to put a subtitle for each column, but the result was that the second column got one row lower than the first. How can I fix this? The page can be found here.

Example code:

<h3>Title</h3>

<h5>Subtitle</h5>
<div style="float: left; width: 350px; margin-right: 5px;">
<ul>
<li><strong>Text</strong>: text, text</li>
<li>second item</li>
<li>third</li>
<li>fourth</li>
<li>fifth</li>
</ul>
</div>

<h5>Subtitle</h5>
<div style="float: left; width: 350px; margin-right: 5px;">
<ul>
<li>first</li>
<li>second</li>
<li>third</li>
<li>fourth</li>
<li>fifth</li>
</ul>
</div>

I need to point out that I’m a newbie at this and I would prefer to avoid modifying the theme if possible.

Thank you for your time.