The Sony VAIO VGN-NR21M/S has a Mobile Intel GM965 Express Chipset which has an integrated Mobile Intel Graphics Media Accelerator X3100.
The display has a resolution of 1280 x 800 (i.e. WXGA).
Did you download and have the Intel Graphics Media Accelerator Driver for Windows Vista installed? This driver is for the integrated graphics controller of Intel chipsets. You can get the driver from Intel's website.