I haven't been messing around with no Quicktime settings either.
Perhaps it is time you did!
These are the downloads and the settings you need in order to view/hear pretty much everything that the net can throw at you: The setup described below has proved repeatedly successful on both PPC and Intel macs, but nothing in life carries a guarantee!
It is known to work in the great majority of cases with Safari 3.0.4, QT 7.3 and OS 10.4.11.
Assuming you already run Tiger versions OS 10.4.9 or above (this has not yet been verified with Leopard) and have Quicktime 7.2 or above, and are using Safari 2 or 3, download and install (
or re-install even if you already had them) the latest versions, suitable for your flavor of Mac, of:
RealPlayer 10 for Mac from
http://forms.real.com/real/player/blackjack.html?platform2=Mac%20OS%20X&product= RealPlayer%2010&proc=g3&lang=&show_list=0&src=macjack
Flip4Mac WMV Player from
http://www.microsoft.com/windows/windowsmedia/player/wmcomponents.mspx (Windows Media Player for the Mac is no longer supported, even by Microsoft)
Perian from
http://perian.org/
Adobe FlashPlayer from
http://www.adobe.com/shockwave/download/download.cgi?P1ProdVersion=ShockwaveFlash
(You can check here:
http://www.adobe.com/products/flash/about/ to see which version you should install for your Mac and OS.)
In Quicktime Preferences, under advanced, UNcheck Enable Flash, and under Mime settings/Miscellananeous only check Quicktime HTML (QHTM).
In Macintosh HD/Library/Quicktime/ delete any files relating to DivX (Perian already has them).
Now go to Safari Preferences/Security, and tick the boxes under Web Content (all 4 of them).
Lastly open Audio Midi Setup (which you will find in the Utilities Folder of your Applications Folder) and click on Audio Devices. Make sure that both Audio Input and Audio Output, under Format, are set to 44100 Hz.
Important: Now repair permissions and restart.
The world should now be your oyster!
You should also consider having the free VLC Player from
http://www.videolan.org/ in your armory, as this plays almost anything that DVD Player might not.