Comment tailoring

I just upgraded to WordPress 2.5 at my site. My theme is veryplaintext 4.5.3.

I have the “Recent Comments” sidebar widget in my sidebar, but it shows links/trackbacks, and the like in addition to regular comments.

For example, if I embed a link to a previous post in the text of a current one, that shows up as a comment in the sidebar.

Is there anyplace where I can set options such that only comments made in a post’s comment section are recognized as comments by the system, and so that only those show up in the sidebar list?

Thanks!