Internal Server Error message - help required

Dear Support team, i am uploading video in http://www.bestindiansexvideos.com and i getting message could you please let me know what should i do? if you want want i can provide you my ftp login so you can check and fix for me thank you.
Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, [email protected] and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
Apache/1.3.37 Server at bestindiansexvideos.com Port 80

Please make sure about the seetings for the upload progress bar is correct.also check
viewtopic.php?f=4&t=1671