mail form

[eluser]Master276[/eluser]
Hi guys,
i'm trying to code my new landing page. I need a form to pick up the mail.

I tried this but i think that is wrong.

Code:

<?php echo form_open('form'); ?>
<input id="mail" type="text" name="mail" value="your email here" />
<input type="submit" value="Submit" />
</form>

have you got some examples or tutorials to share with me?
Moreover....i've got some doubt about the interaction with the Db...i've to define it in my controller right?

thank you guys