A disambiguation page is a page which helps sort out articles which have similar names or are potentially confusing. For example, there have been several people called “Angel” within the various comics that Marvel has published over our 70-odd year history. The disambiguation page for Angel_(disambiguation) helps people visiting the wiki find the exact article they are looking for.
To Create a New Disambiguation Page:
Many disambiguation pages use mediawiki gallery tags to show a visual guide of the various characters to which they link. You can get more information on building galleries here: http://www.mediawiki.org/wiki/Gallery#Gallery_of_images