Persistent crashing of Flash plug-in in different browsers

Question

_________Problem Specification:___________
Whenever I click:
'Attach' on Yahoo Mail, or 'Bestand toevoegen als bijlage' on Gmail (this is the Dutch version of the attach funtion for Gmail), or 'Add more photos' on Facebook (or similar functions of FB where you can upload photo's), or the normal upload screen for Youtube and a couple of other websites that have functions to upload files I get notified of this:
'De Adobe Flash-plug-in is gecrasht Meer info...' and two buttons on the right side: 'Pagina vernieuwen' and 'Een crashrapport verzenden'.
This of course reads: 'The Adobe Flash plug-in has crashed. More info...' and the buttons say: 'Refresh page' and 'Send crash report'
This particular error message occurs in Firefox (version info below) and 'More info...' takes me to a very generic Mozilla troubleshooting site, which suggests to update Firefox, the Flash Plug-in, Graphical card drivers (if I'm not mistaken) and a few other things.
In Internet Explorer I get an error at exactly the same time as I get it in Firefox, only IE quickly reloads the current tab and then gives you a little notification about that, it seems to persistently occur at exactly the same points as when they do in FF though (when I click 'Attach' etc.)
_________What I tried to do:______________
I Tried:
- Reinstalling Firefox
- Reinstalling Flash (by removing it in add/remove programs in Windows and then reinstalling it by downloading it again and then installing it)
- I disabled hardware acceleration (Flash seems to function fine when playing Youtube and similar videos, above mentioned problem persists)
- In about:config in FF I changed the options around for IPC (as mentioned here: http://kb.mozillazine.org/Plugin-container_and_out-of-process_plugins )
- I made sure that all applications running (such as firefox.exe and plugin-container.exe) that are associated with what I'm trying to accomplish are marked as safe in my security software (Comodo)
_________Technical Information:___________
Operating System: Microsoft Windows XP [versie 5.1.2600] (that is the Dutch language version of XP + SP3, alternately it is described as: Microsoft Windows XP Professional Versie 2002 Service Pack 3, we're talking the 32 bits version of windows.
Web browsers tried: Firefox 3.6.12 (Dutch version)and Windows Internet Explorer Version 8.0.6001.18702
Flash player version: Shockwave Flash 10.1.102.64 Shockwave Flash 10.1.r102
I run this on a laptop with a 64 bit AMD Turion processor and a built-in ATI Radeon Mobility graphics card.
So what's next?

Answer 1

First of all, let me thank you for your suggestions so far.
I tried the safe mode and I looked into the graphical card drivers
In Internet Explorer Attaching with Gmail with Safe Mode now brings up the file dialog that I'd need to attach files. So this seems to be a viable workaround, although it's also possible to change Gmail to the simple HTML version where the dialog would come up anyway in both browsers, this is because the dialog in the simple HTML version is a standard Windows dialog and it's not Flash based.
In Firefox there's no such luck, the same message about the Flash Plug-in crashing appears under the same conditions.
Btw I double checked the HP support site (the manufacturer of my website, to which I was referred by AMD) and I do have the latest graphical card drivers installed, as a matter of fact I've been having this Flash player problem a while now, even from before I updated the drivers the last time, which was approximately a week or two ago.