.php files not opening on Localhost

[trhoades]

When I try to open http://localhost/phpinfo.php I get a download prompt asking if I want to open or save the file. 
 
I think it happened while trying to load phpMyAdmin.  Everything was working fine before I tried to set up phpMyAdmin, which I still have not managed to setup.
 
Novice at work here.
 
Any help would be great.  I'm lossing sleep over this.
 
Thanks,
 
Tony