Replacing Menu Link Name

[mac10]

How to replace the menu link names on the code:

Original code:
global $root_url,$lcl;
return '<li><a href="'.$root_url.'">'.$lcl['homepage'].'</a></li>
<li><a href="'.$root_url.'">'.$lcl['videos'].'</a></li>
<li><a href="'.$root_url.'?option=popular">'.$lcl['popularvideos'].'</a></li>
<li><a href="'.$root_url.'?option=contact">'.$lcl['contact'].'</a></li>';

to this:

global $root_url,$lcl;
return '<li><a href="'.$root_url.'">'.$lcl['Home'].'</a></li>
<li><a href="'.$root_url.'">'.$lcl['Videos'].'</a></li>
<li><a href="'.$root_url.'?option=popular">'.$lcl['Popular Videos'].'</a></li>
<li><a href="'.$root_url.'?option=contact">'.$lcl['Support'].'</a></li>';

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Every time I replace the link names, the link disappears. Any help would be awesome!

Thanks