blimey - great design - now that is making it your own. now some so and so will probably tell you that you have validation errors and they may tell you to fix them up, but I checked your site in IE and FF and they look great. Not sure about safari or opera though.
Some of the errors are simple anyway, like using span id="b" several times throughout - remember id's are UNIQUE. Classes can be used multiple times, so just change that from span id="b" to span class="b".
In actual fact about 90% of yoour errors are id errors - repeating the same id, instead of setting them as classes. the other lot are some SGML but that's language based I think and finally not using alt="enter image description here" for your images.
But AGAIN, your site looks good in both "main" browsers so it doesn't bother me too much :)
in case it does pique your interest: