Yes, among the most common frustrations of Mac users new to the p2p is movie playback.
You see, I learned (through these here forums) that video (and audio) are encoded into data files using somethin called codecs.
The problem is that there's a whole variety of them out there and some are available for some platforms while others aren't and some are available for some players while others aren't. To be more specific, Quicktime has trouble playing some of these (some .mpg and .avi) because it lacks the right codecs.
Now, instead of opening up Safari and going for a hunt for these elusive codecs, download this player: http://www.videolan.org/vlc/download-macosx.html (you may also download this one: http://mplayerosx.sourceforge.net/ ). This way you don't have to worry about codecs anymore (well, maybe a little) 'cause this here player can play most everything you throw at it.

Note: the second player (mplayer OSX) has a better image quality and, depending on tastes, better controls than VLC (the first one) but it feels kinda incomlete as it lacks certain features, like having a subtitle-select function for .ogm files. My primary player is VLC but mplayer will generally play files a little more smoothly while also slightly increasing the image quality.

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iMac G4 OSX 10.3.9
RAM 256MB
LW 4.10.5 Basic
ADSL anything from 3 to 8Mbps/around 1024kbps

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