I have WP installed on numerous hosting sites and recently installed it on my Godaddy hosted sites and it choked. Continuous "500 Internal Server Error" messages. Not only would I get these messages, my pages consistently load extremely slow. I called Godaddy tech a number of times with no luck of a solution. Yesterday morning I opened a ticket and got an immediate response.
"Thank you for contacting Online Support. It appears you are getting internal server errors on your WordPress site. Upon reviewing your account, I am going to suggest that you upgrade your hosting to our 4GH plan, which offers improved performance. For more information, see 4GH Frequently Asked Questions."
I upgraded my hosting "for free" to the 4GH, my WordPress sites on Godaddy are flying.
Apparently the way 4GH server grids manage and share processor demands and loads made the difference.
I hope this helps someone else, SHANE