Module development and code questions

I'm having trouple with this piece of code:

Is there any module for Drupale to manage mailing lists?
I need ability to mass mailing for site subscribers.
What module are used for drupal.org mail list?
Thanks.

It bugs me sometimes that Drupal will just cut at a part in your node, without letting the user know something has been cut. So... here is what I did to fix that...
Open up node.module in your favorite editor and search for 'function node_teaser($body)'.
You should see some sections that look like this:

return substr($body, 0, $delimiter);

Replace all of them with something like this:

I have modified XTemplate to produce a new fixed-width layout,
and all works fine but locale module which is stretching the layout.

Not on it's first page, but after search when it populates the table with
locale terms.

Looking at the HTML output I can see where the problem starts, but I just can't
find the solution, tried everything I could think of for the past 2 days. Now I am really getting desperate.

HTML Output looks like this:

<div id="help">The locale module handles translations into new
languages. It also enables you to add jargon,
slang or other special language as fits the web site.
For each language you want to support, a line needs to
be added to your configuration file.<br>
&lt;/div&gt;

This part is still OK, and now the problem follows:

<!- begin content ->

<table >

<tr><th>string</th><th>languages'</th><th colspan="2">operations</th> </tr>

<tr class="dark"><td><br /><small><i>/beautymag/admin/system/modules</i></small>
</td>
<td
align="center"><strike>hr</strike> <strike>en</strike> </td><td
nowrap="nowrap"><a href="admin/locale/edit/399">edit
locale</a></td><td nowrap="nowrap"><a href="admin/locale/delete/399">
delete
locale</a></td> </tr>

I have run into problems applying patches, as follows:

node.module:

patch < node.module.patch
patching file node.module
Hunk #1 FAILED at 1245.
1 out of 1 hunk FAILED -- saving rejects to file node.module.rej

node_image.module:

patch < imaged_nodes.patch
patching file node_image.module
Hunk #1 FAILED at 184.
Hunk #2 FAILED at 582.
2 out of 2 hunks FAILED -- saving rejects to file node_image.module.rej

xtemplate.theme:

In my module settings how do i create a dropdown that selects a different taxonomy vocab?

Thanks