You could have php or another scripting language create a HTML file for you, but that would be superfluous if you could do with a php file that reads in your browser like a HTML file does. So ask yourself the question: is it worth the trouble to get a HTML file?

If you click on the rss link in your blog you get the RSS page, probably that's what you want.
To generate a php file, all you have to do is strip the _main.php file of a skin down to the RSS part:

	<div class="bSideItem">
		<h3><img src="<?php echo $rsc_url ?>icons/feed-icon-16x16.gif" width="16" height="16" class="top" alt="" /> <?php echo T_('XML Feeds') ?></h3>
			<ul>
				<li>
					RSS 0.92:
					<a href="<?php $Blog->disp( 'rss_url', 'raw' ) ?>"><?php echo T_('Posts') ?></a>,
					<a href="<?php $Blog->disp( 'comments_rss_url', 'raw' ) ?>"><?php echo T_('Comments') ?></a>
				</li>
				<li>
					RSS 1.0:
					<a href="<?php $Blog->disp( 'rdf_url', 'raw' ) ?>"><?php echo T_('Posts') ?></a>,
					<a href="<?php $Blog->disp( 'comments_rdf_url', 'raw' ) ?>"><?php echo T_('Comments') ?></a>
				</li>
				<li>
					RSS 2.0:
					<a href="<?php $Blog->disp( 'rss2_url', 'raw' ) ?>"><?php echo T_('Posts') ?></a>,
					<a href="<?php $Blog->disp( 'comments_rss2_url', 'raw' ) ?>"><?php echo T_('Comments') ?></a>
				</li>
				<li>
					Atom:
					<a href="<?php $Blog->disp( 'atom_url', 'raw' ) ?>"><?php echo T_('Posts') ?></a>,
					<a href="<?php $Blog->disp( 'comments_atom_url', 'raw' ) ?>"><?php echo T_('Comments') ?></a>
				</li>
			</ul>
			<a href="http://webreference.fr/2006/08/30/rss_atom_xml" title="External - English"><?php echo T_('What is RSS?') ?></a>
	</div>

If you leave the links out (delete the <a href=" part) then you have direct access to the RSS feed.

That's about all you have to do.

Good luck

AFAIK this won't work on a .html page because php is processed on the server and html is passed to the browser. Therefore the bits that make the feeds happen won't happen if they're not on a .php page.

You would want to copy the source code from your php-generated blog page and paste it into your .html page, assuming what you're looking for is a way to say "here are my feed links" on a .html page.