The DWL file is a lock file and prevents AutoCad from opening anothe copy of a drawing you already have open. You should not have to worry about this. It is usually automatically deleted when the drawing is closed. If not, you may have to manually delete it.
If you want to update the text in a title block just double-click the title block. The attribute editor should open.
If you want to change the look of the title block you can edit the block in the drawing using the command BEDIT. It is better to edit to original template, if you have one. Or create one.
