I'm not sure I understood your question, anyway why not have only the table on the page?http://spreadsheets.google.com/pub?key= ... utput=html
You can do right-click and "View source" then select and copy the whole code and paste it into an HTML Snippet as it is. Hit Apply. However the formatting will be all messed up and look bad.
You can also take only the <table></table> part and paste it into the HTML Snippet (without the iFrame code, in an iFrame code you can only add URLs no other HTML code). Just take the <table></table> code and paste it in an HTML Snippet as it is. However this way too the table formatting will be messed up.