I cannot answer your question fully, except offering you a point or 2.............
It's late to say that now. For your future reference, whenever you do OS upgrade, you should check with Upgrade Advisory to see if your PC is ready for OS upgrade.
In this case, you would use Windows 7 Upgrade Advisor
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1. XP drivers usually will not work on Win 7. So, you will need to install or update your drivers. Go to your computer manufacturer website and check for drivers updates.
I think drivers issue is your culprit.
2. Programs that run in XP may not be able to run in Win 7. You will need to check out the compatibility.
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