As 18.104.22.168 is only a minor release, and not a major version.
It is ok to do upgrade using the Magento Connect Manager
Just check for updates, it will show 2 items as requiring updates.. and just install the 2 updates
Thats all I did, and not had any problems.. just cleared the cache and sessions as a precaution.
22.214.171.124 doesnt effect your themes and things and it will leave those untouched. only thin g it will effect is if you have modified the core files in any way.
this might help, https://www.properhost.com/members/knowledgebase.php?action=displayarticle&id;=1