Help needed desperately !

I have a laptop which is currently running PSE3 and it works perfectly. Sadly I also have a PC and I cannot get it to run on there for love nor money. Every time I try to get it to work on my PC I get an error message stating "Adobe P.E. requires a screen resolution of at least 800x600 pixels and colour quality greater than 256 colours". It would appear that the Adobe software is somehow reducing the resolution of my monitor ?
I have also had one error message stating that the software was attempting to change the registry on my PC ?
Any help would be more than appreciated.
Thank you.

Not sure if I can solve this, but it would be useful to describe the PC you are having trouble with - OS, memory, processor, video card? Double check the settings for video by right clicking on the desktop and clicking "Properties" then "Settings" - verify those exceed what PSE is calling for. If they do then I don' understand, if they don't then change them or upgrade PC/video if they can't be changed.

BTW it isn't trying to change the monitor resolution, it is demanding a minimum level of setting/quality from the video card (or built-in video).

Mark, it is a fairly new Dell PC with 275 Gb free hard drive space. I am running Windows XP Sp2 and I have an ATI/Radeon graphics card.
When I double click on the PSE icon the screen goes blank, temporarily, and then returns with a slightly pixellated look. If I then click on any of the functions of the PSE software I get the error message.
What I really do not understand is why it works on my laptop and yet will not work on my PC. Both laptop and PC are running exactly the same Internet Security software, F-Secure. I did ask F-Secure about this problem and they replied saying that my display card driver was not installed correctly. I then tried to download an update and got the following error message, "Application Install, install package not supported on this platform".
Hope this helps.

I presume your video settings exceed those listed in first post (hard not to with any modern PC). I'd completely uninstall PSE, then try updating video card driver - make sure you get the right one for XP, then reinstall PSE. Here's where I would look for the drivers http://ati.amd.com/sup​port/driver.html.

Thank you very much for your help Mark.