you can remove tags with strip_tags().
Also worth to have a look at htmlentities().
As for regexps,
i'm used to preg_* functions (they are supposed to be faster)
$text = preg_replace('/<.*?>/', '', $text);
In ereg_ it should be like
$text = ereg_replace('<.*?>', '', $text);
(or eregi_, doesn't matter). But maybe i have some minor syntax error here.