Looking at the source code I'm not sure you've got the Style sheet set up right.
You seem to have 5 style sheets on each page - you only need one and put all the styles in that one .css file.
If you look at ahover.css you will see the following is in there:
whereas alink.css is
So when you hover your font is changing down by 2px and becoming italic. This is why it looks odd.