seacue, would that be a Dell Inspiron 1420 by any chance as I had exactly the same issue with it when installing a standard W7 Professional.
I often aquire old laptops fix em up and give them away for free to people who would otherwise never buy a computer. In this case getting W7 Professional to install on this Dell was a real PITA.
From memory, I fiddled with BIOS, downloaded the latest drivers from Dell, but what I vaguely recall fixing it with was using a tool called something like Universal Windows Boot System (or something similar) to reformat the hard disk at low level and install a standard Master Boot Record. I have a feeling that Dell systems by default require Dell OEM W7 to install, and to defeat that you have to overwrite the ugly bits on the hard disk, maybe someone with more expertise with Dell could elaborate.
It took quite a while to get W7 Professional up and running, and after all that effort the W7 licence key I was provided didn't validate and was going to expire in 1 month. Buggah, so I stuck Linux on it instead
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