It looks okay. I don't speak Portuguese or Spanish (just English and a tiny bit of French), but the translations were good. The links seemed okay. I used "HTML Tidy" to check validation; there were only minor problems. I suggest going to the W3C validator (
http://validator.w3.org/) to clean up the last little bit.
If you're interested in some major changes, I would suggest
"Magento", a shopping cart application that can use "Paypal" and more. I always go to
Sourceforge first for my software needs.
~Curtis
(hover over some of the site and software names for links)