It sounds as if the cursor is incorrectly describing its position to Vista's vector graphics rendering engine, different from all previous versions of Windows, which are pixel-description based.
I'm not sure this is a hardware issue. I doubt I would like to see my brand-new PC acting in this manner. Ask for an RMA based on the problem, unless they are going to fix it. If they ask you to send it in, bite the bullet and do it. This is an expensive PC, and should be perfect from day one. Demand satisfaction.
If one Dell rep is not helpful, call back and talk to another. Different reps have different personalities and interest in their job, you just to need to find someone to take ownership of the problem. Don't be nasty, be firm and calm, and say you would like a new PC because you were told this is an endemic problem. It may well NOT be, but I wouldn't want to spend this much coin on a new PC with birth defects.
Tony
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