I think I may havesome additional info which makes the waters both clearer and mudier.
If I setup my ftp client to ftp into 126.96.36.199 (the address from a previous) my ftp client logs in but REFUSES to allowme to do anything because of a permissions issue.
My gut feeling is that Neil is correct you need to contact your ISP and get the correct settings.
For all of my sites the format is the same:
Username is: thedomain name ie edwards-micros.co.uk
the ftp address is ftp.edwards-micros.co.uk
the password is 123435
and the host directory is /htdocs/
THis is on both my windows and Unix servers
Take a look at this link
it shows the settings required for sucessfull FTP connection.
If you still fail then I can only suggest that you privately email the details to me or support if they are willing and let us try to resolve your issue.