così non da errore nel validatore, ma non mi fa vedere l'immagine di sfondo... ho messo:

style="background-image: images/barra-home_r2_c9.jpg"

nel tag della cella...

in più mi da errore in una tabella e mi da:

Line 199, column 64: document type does not allow element "TABLE" here; missing one of "APPLET", "OBJECT", "MAP", "IFRAME", "BUTTON" start-tag

...rder="0" width="100%" cellpadding="0" cellspacing="0"><tr><td valign="top" width="52%">

The mentioned element is not allowed to appear in the context in which you've placed it; the other mentioned elements are the only ones that are both allowed there and can contain the element mentioned. This might mean that you need a containing element, or possibly that you've forgotten to close a previous element.

One possible cause for this message is that you have attempted to put a block-level element (such as "

" or "<table>") inside an inline element (such as "<a>", "<span>", or "<font>").