ciao ummm I've been watching the shows on Youtube and just wondering whats the episode be...

ciao ummm I've been watching the shows on Youtube and just wondering whats the episodes before the ones called Return To New York? apparently Shredder is back and kicks their shell and I want to watch it before I watch Return To New York!?
P.S. if te know PLEASE spare some of your time to help me?
P.P.S if te know what channel and time and if giorno I can watch TMNT on TV?