Post installation

Hi,

I am hoping someone can point me to a module or settings that allow me to do the following:

Tabs in the header. As in the nice tab style menu at the top of drupal.org.

I instructed Drupal in case of error to give visitor pages 404.shtml and 403.shtml which I created.
I entered paths to these pages in administre/settings/Error Handling
But Drupal still shows another page which it makes himself: Drupal takes page template and insert "Page not found" title in it. How to fix it?
Version:4.6.8

Thanks to an error in the PHP code included in one of my blocks I've realized the block is executed on all pages, regardless it is visible on a specific page or not. Isn't it strange? The code embeded in the block restricted to just a single page is always executed, even on pages that don't exists (404).

Is this normal behaviour or is something wrong with my Drupal implementation?

Thank you,

Marek

Problem 1:

I have a hard time creating users for the community around our school, as several of them, shares a single email address (family emails). When I try to create an additional user, I get this error:

The e-mail address "familyname@mailserver.com" is already taken.

Problem 2:

For some reason, users WITHOUT "administer nodes" access get returned Access Denied or Not Found errors.

So, when I enable "administer nodes" access for all users, everyone can see the nodes.

Any ideas on solving this?

Is there a definitive method for applying module patches? I've seen discussions with patches listed in them but can't work out how to apply them. I assume there may be a page somewhere with this info on but I can't find one.

TIA
Glenn Williams