I have a static page on my front page and when I click to the posts everything (header and category boxes) are a few pixels off. Here you can see it in action:

http://www.vanessaskiles.com/

Click back and forth from the main page to any of the categories (2012 for example.)

I see no difference on my ipad

Wow, that is odd. I just tested it and it does not shift on my ipad either. But it does on mine, and my husbands computer in Chrome and Explorer. It shifts about 15 pixels left. And it leaves a little pixel line on the right side of the category buttons.

I took a screenshot of the line, and it hops to the left 15 pixels or so from the static front page.

on my mac in chrome, firefox and safari it all looks the same

How odd, well thank you for trying, twice. Not sure what's going on with the PC viewing it....

Edit: Had two friends on PC's look and they too saw the slight shift to the left. Any ideas? I've tried googling about and can't find anything.

Finally saw it when I zoomed out in the browser. Try this, add the following to the css inserts

div#menu2 ul.rMenu {
background: transparent;
}

Well, that got rid of the line, so that's huge. There's still an offset, but at least there is no lame line there. Thank you so much!

Not certain but you might try putting padding: 0 on that same CSS - EG

div#menu2 ul.rMenu {
background: transparent;
padding: 0;
}

No luck on the padding, thanks though!