Different look in Opera and IE<9

My site looks the same (for me that’s correct look) in FF, Safari and IE 9. link
But I have some problem with Opera (divs in the middle of the page aren’t centered) and IE<9 (just take a look).
I’d be very grateful if you could point me where can be the problem with the code…

It looks fine in Oper to me. But I dread to look at an HTML5 site in IE8 and under. I see you are using Modernizr, but all the same, using these new elements doesn’t seem worth the trouble to me. It’s really important to test a page in browsers as you build it, as debugging once the page is finished is much harder.

In Opera the boxes in the middle and at the bottom (dogs pictures and everything under it) are not centered properly. I don’t know why.
Do you think it’s to early to use html5 elements concerning IE?

I’m not sure how well IE9 supports the new elements, but IE8 doesn’t, and it will be a good while before that gets killed off. So the new elements only really survive on a CSS/JS life support system, which I find untenable—though many people don’t, to my surprise.

As elements gradually become supported, I’m sure I’ll use them. But IMHO there’s no point whatsoever to be using new elements like <nav> and <section> right now, as they offer no structural or semantic advantage (because browsers don’t understand the semantics yet), while at the same time the bring with them a bunch of headaches.

Maybe you’re right about the html5 elements…Although I made html5 sites that looks great in IE…
And what about Opera? Do these boxes look good for you? I think there’re not centered properly.