Dunno what caused it, but I think it may be fixed by "tuning" the monitor's gamma... eh.. what model is it?

Start> Control Panel> Hardware and Sound> nVidia Control Panel... or perhaps any other option that my help you tune monitor color in case you don't have an nVidia card ... still if it doesnt work you should try uninstalling the printer (if it installed) o removin any leftover files... To me it has a lot to do with the software that handles monitor color (since it doen't affect the startup or closing) so perhaps you should try tuning it first before doing anything else..

i would try using the auto config button located on your monitor if it's new.
your graphics card seems new too so i dont think there will be a hardware issue.
also it seems strange to install printers with an XP disc.
anyway i would reccomend changing your monitors phisical settings.
and by bright do you mean high contrast or just a high brightness setting ?

What programs are loading at startup?

Well, here's an idea to see if it can be narrowed down to a startup item. Run msconfig and choose Diagnostic Startup. Restart and see if you still get the bright screen. Don't forget to put back Normal Startup when you are done.

This is a desktop machine, yes?

burnsie, that proves that something running at startup time is causing the bright screen. Next, you could run selective startup, disabling half the items and then the other half. Keep narrowing down until you find the one that does it. That's a bit brute-force but it's almost certain to work. The more elegant way would be to make educated guesses about which task is the culprit, or post your startup list here and let us have a look.

ThankYouVeryMuch! [bows]

burnsie, glad it's all fixed now. Cheers!