I downloaded an episode off of limwire and I keep trying to play it and the sound nor the picture will work with quicktime and I don't know why! I'd appreciate it if someone helped! Thanks!
VLC is free but if you want to use QT just download and install: XviD Avi Import Intel (http://n.ethz.ch/student/naegelic/download/XviD_Avi_Import_Preview4_intel.dmg) DivX 6.5 (http://download.divx.com/divx/mac/DivXInstaller.dmg) A52Codec (http://www.versiontracker.com/dyn/moreinfo/macosx/27300) Flip4Mac 2.1 (http://www.flip4mac.com/wmv_download.htm) Now you should be able to play .avi, .avi with AC3 sound and .wmv files with QT
I just realised that I assumed you had an Intel Mac. If you have a PPC one get rid of the XviD Avi Import component and get 3ivx D4 4.5.1 for OS X (http://www.3ivx.com/download/macos.html).