how would I best wrap my entire node in an tag linking to the full node? My nodes are display using Display Suite and a custom view mode.
I'm guessing creating a php template and manually writing the link somehow would work?
A good option for this is Field Group Link.
For your case, basically you need to create a field group wrapping the whole node, and set the group type to 'Link'.
When you go
/admin/structure/types/manage/blog/display/teaser (or whatever content type you're going for) at the bottom is a list of possible template names. In my example
ds-2col-stacked-fluid--node.tpl.php was what I needed.
In the template file I ended up wrapping my content variables with the following:
<a href="<?php echo url('node/' . $nid); ?>"> normal node here </a>
One thing to note is that you need to make sure there are no nested links around fields like image, author or title.