Welcome to the forum Mark.
I suggest you only use the Dell drivers. I have a Precision laptop with an NVidia card and only the Dell drivers work properly. NVidia drivers directly from NVidia cause serous artifacts in auxiliary windows regardless of version.
Yes the E series is an office model and the Nvidia NVS seris is not supported by PTC. The M serries would be your only way. And I concur that you should not even considder 32 Bit as an OS on the M Serries. I find it hard to believe that ANY 32 bit app would not work on the 64 Bit platform. It should still be able to be installed and run.
I'm not sure if you already purchased you machine or if you are still shopping but here is Platform Support page:
For Creo Parametric 2.0:
If a machine configuration is not listed on the Platform Support page it does not mean neccessarily mean there will be any issue. Many untested machines perform just fine (sometimes better ) but the specific ones listed have been tested and certified by PTC and will be supported.