One of the plus/minus factors in the social media universe is the immortality of material that you post on the web. If you write an ill-advised comment on someone else’s blog, it’s there forever (unless you convince the blogger to remove it). However, the same isn’t true of a blog you write yourself; it’s not hard to hide your blog from public view or delete it completely.
If you haven’t posted anything to your blog in a long time (definition of “a long time”…maybe 6 months?), it’s debatable whether the blog is an asset to your networking or marketing efforts. If you use WordPress, you can hide your blog by going to Settings>Privacy and then selecting the most restrictive privacy level, where you must approve each user who can view your blog. If you want to delete the blog entirely, go to Settings>Delete blog. Note that at least in WordPress, deleting your blog is irreversible. If you have *any* inkling that you might use your blog posts for something in the future, either just hide the blog as described above, or back up the blog to an XML file before you delete it (in WordPress, go to Tools>Export). Or better yet, start blogging again!