Photoshop Elements won't open

Question

I've been using this computer in my workshop for simple things, mostly email, fb, etc. It has had Photoshop CS (very old, not sure what version) and Photoshop Elements 2.0 on it and both have been working fine. Just brought it into the house to use in the office after my slightly newer, but still old, iMac G5 died. I'm hoping to use it for a short time while figuring out what to do next regarding a newer computer. I've gotten it connected to printer and scanner with a bit of trouble due to trying to find old drivers again. That's really all I'm aware of having changed. Now suddenly PE and P CS won't open. I reinstalled PE (which is what I use most); no change. It starts to open, then just quits. I've clicked on "report" and see the following:
Date/Time:      2012-04-11 00:02:41.529 -0400
OS Version:     10.4.11 (Build 8S165)
Report Version: 4
Command: Photoshop Elements 2.0
Path:    /Applications/Adobe Photoshop Elements 2/Photoshop Elements 2.0/Contents/MacOS/Photoshop Elements 2.0
Parent:  WindowServer [66]
Version: 2.0 (2.0)
PID:    246
Thread: 0
Exception:  EXC_BAD_ACCESS (0x0001)
Codes:      KERN_INVALID_ADDRESS (0x0001) at 0x6f726b2e
Of course there's lots more but that's the part with the bad words like "bad access" and "invalid address" and such. I'm hoping someone can tell me what is going on; perhaps you know what the above means? Or maybe there is some other clue here? I'd be grateful. Thanks for reading.
Judy
PS Just to be clear, no major changes in software; I have been running both Photoshop programs on this computer, with OS 10.4.11, since getting the computer as a hand-me-down a couple of months ago. I did update OS, Safari, and a few other things at that time, as well as maxing the memory, deleting many programs and files I'll never use, etc. Installed PE 2.0 at that time. CS was already on it. Both have worked just fine. When I reinstalled PE the installer said it had installed properly.

Answer 1

Well, just in case someone else checks in here with the same problem. Got both programs working just fine again. I hunted up other threads on the same topic; several had posts suggesting trashing certain plug-ins and/or prefs. I'd tell you exactly what but I did a bunch and not sure which solved it. With Photoshop CS 8.0, I deleted plist in user library; no change; then deleted twain plug-in, now it opens just fine. I don't exactly comprehend why, but so far so good. If I have any other useful observations I will post them.
Judy
PS I ordered a PRAM battery and will replace that anyway, just because I'm certain it is quite old; perhaps this will prevent other problems popping up. I need to get a bit more use out of this nice old machine!