I'm new at this so, it's a bit hard to understand.
... i have no idea what you meen by this?
with this level of technical understanding, you might need to consider to hire somebody - http://jobs.wordpress.net/
how did you create the page with the sidebar problem?
the helpers here in the forum can only see the generated code, but cannot look into your templates; therefore we can only ask questions to guide you to solve the problem.
from looking at the html of the faulty page, and the validation report, it seems that there are some unnecessary html tags; but you need to find out in which template these are.
But if i change excess is removes al my products..
where and how did you do that?
can you post the full code of the template you are working with?