Gimp / Inkscape tablet issues (wrong co ordinates in the program)

Hi there, I do not know who to turn to regarding this problem, I hope I am posting in the correct place. If not, please could someone point me in the right direction?

I am a digital artist / computer technician and have been using GIMP for the last 2 years, I've never had much issues with it and recommend it to many of my artist friends to try, I've recently tried out inkscape but am still getting used to it

I have googled around for a solution to this problem, I only found more questions than answers

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Using: GIMP ver 2.6.7 with GPS and GAP
OS: Windows XP Pro SP3
Tablet: Genius Mousepen 8 x 6
Display: 20" LG flatron @ 1600 x 900

OK, what's happening?
- I have a Windows XP machine here, and I was using a 19" CRT monitor on it up till the day before yesterday.
- Yesterday I acquired a shiny new 20" LCD. I installed it and continued working as normal.
- I got the clever idea to try and set the two screens up as a Dual View on my Nvidia card.
- My Genius 8x6 Mousepen tablet operated as normal in Windows itself and general programs
- Then I opened up GIMP to do some work and the strangest thing happens.

(I managed to find a video on the net with my issue, but no solution, I think it's the best way to explain the problem here)
http://video.google.com/videoplay?docid=-963158980122070242#

-I have tried updating the tablet drivers, even the display drivers and that didnt work.
-I have tried the Input Settings in Gimp, that did not work
-The only thing that brought me a minor amount of joy was completely removing the tablet driver, but then I have no pressure sensitivity and I require it for my work.
- I finally decided to remove the second screen and just use the LCD one. GIMP is now having that exact problem on my single display as well.
- I uninstalled GIMP 2.6.7,
- I downgraded all the way down to Gimp 2 to see if it would help if I reinstalled it with the manual GTK install. Same problem
- I reinstalled Gimp 2.6.7, finally got the "must restart your computer" screen i wanted, but upon restart still the same thing.

This problem is persistent between both GIMP and Inkscape, perhaps other GTK programs too.
I reckon it must be a problem with the GTK, since SAI Paint, and Photoshop are working perfectly.

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If there is perhaps some kind of Dual monitor issue, it would be very nice to be able to have that ability in future versions.
For an artist like myself, I use GIMP at least 6 hours a day, and I would like to have the ability to have my IM programs, reference pictures or perhaps even a movie playing in the other monitor while I am drawing on the main one.
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At this moment is looks like a complete Windows wipe is the solution, which I really dont want to do

I would greatly appreciate any help I can get, I do so love my GIMP and will continue supporting and using it

Thank you very much
-Cat