Dvae

Hopefully someone could shed some light on the following:
I would like to link a post title to an an external url like you would in a link list.

I would also like to link a thumbnail to a single post.
For example, if I click on an archive month that then displays posts to match that month, the body of the message contains an excerpt of the full post and a thumbnail.
What I want to do is click on the thumbnail, and go to the full post. The only way I see to do that now is to click on the post title.