What video codecs are supported on my tv ( model LN40C530F1F)?

When I download digital videos onto my external hard drive and try to initiate them on the tv’s media play, most show up but others do not. What video formats/codecs are specifically supported on my tv model and can the firmware be changed or added to support a wider variety of formats/codecs?

What WIFI dongle do I need to get that goes with Samsung TV?

I would like to connect my Samsung TV to my home network. I have a lcd hdtv 503 series 1080p (LN40C503FiFXZA) Which dongle should I get? Or should I do it another way?

How can I play my music from iPhone through my TV?

When I hook up my iPhone to the USB hook up, the TV recognizes the phone and I am able to see my photos but when I try to play music I get an error message that there is no music on the device. I have a 40" Class 530 Series 1080p LCD HDTV