It should work fine with Windows 7 32 Bit. As you managed to install Windows 7 64 Bit you have a processor that is 64 Bit capable so it'll work for both.
What drivers did you use for video?
Dell don't list Windows 7 drivers but I pieced together updated drivers and listed them here:
P.S if you have already went out and bought Windows 7 64 Bit you don't need to buy Windows 7 32 Bit, the product key is valid for both versions but I recommend installing the 64 Bit version where possible.