Imac G5 Freeze


My iMac G5 is freezing on start up. It gets to the desktop, but the furthest it gets before freezing is when the icons start bouncing in the dock. Whether the freeze has anything to do with my attempt to send a fax just before the first freeze, I have no idea.

In panic (and on the advice of a message board) II tried starting it up while holding down the PRAM keys (not knowing what this would do). I seem though to get marginally morer progress starting up while holding down the shift key (extensions?) but still the software bouncing in the dock won't launch.
Hmmm, being provided the MacOS X installed (such as 'Panther' 10.3.0 - 10.3.9, or 'Tiger' 10.4.0 - 10.4.2), on the iMac G5, would be really nice.

Nor mentioned was whether you were FAX'ing from within an application using the MacOS X'es built-in FAX capability; or, if you installed a third party FAX application.

Also, stating 'the software bouncing in the dock' is not as helpful as listing the actual application's name.

So, how about replying with:
Your Mac's currently installed MacOS X name ('Panther', 'Tiger', ...) and version number ('10.3.4', '10.4.0', ...),
A 'Yes' / 'No' answer as to whether you were FAX'ing with MacOS X'es built-in FAX feature. If 'No' please supply the third party application's name and version number).
The name (and possibly its version number) of the application(s) whose icon(s) bounces during boot up.