what software is needed for video
 

a message popped up when i attempted to open a commercial i downloaded. the message said something along the lines of not having the software needed to play the clip. i have both REal Player and Quicktime....what am doing wrong? help please

Try www.videolan.org for a free player that plays almost any file, depending on your O.S.

you lost me on the Nemo's codec pac. where would i find that? i have a mac-does that matter? is there something in my preferences that i need to change?
thank you for you help.