make sure that you have internet on your account, then about the sock 4 sock 5 question, jus leave it at sock 4...theres no need to enter the user name and password in the proxy settings, jus leave them blank...what will happen sometimes is it will connect but after connection it may go back to the original sprint connection, to solve this either flash over a custom rom or give this a try
http://forum.ppcgeeks.com/showthread.php?p=248866