Your text is very close to the edges of their boxes. Look at using margins and padding to provide a bit more space around the text. Typical blog designs would be a good source of inspiration for this type of site IMO.
1. Fluid width/Fixed width? - from the content it appears that your site would easier to read with a fixed width. The main content lines get very long on wider screens.
2. The font sizes don't seem to have any consistency, and the main body font seems too small.
3. The right column is at least half the width it needs to be.
4. I wouldn't call this site "designed" at all, there are little, if any design elements to it. It's your typical header/3-column/footer layout maintaining basic boxes and solid color blocks.
I would definitely add some padding in those columns. Looks too cluttered at present. I would also set your margin to 0; and remove that white space at the top of your layout. Doesn't look right to me.
Also your page currently has no Doctype and therefore isn't valid at all. Maybe try to make your page compliant with standards.