Older Posts Link

In the Adventerous THeme I have put a WIdget on the sidebar with Recent Posts in it. The theme has an older posts link way at the bottom of the page. I am using full content, not exerps with readmore buttons. Is there an easy way to add an olderposts link to the Widget for recent posts without changing the code in the editor. THis would be HTML code not "Custom Css" Or do I just need to go find a plugin that shows both the newer posts and an older post link.