Nikon D2Hs has a
4.0MP APS-C (23.7 x 15.5 mm ) sized JFET sensor . On the other hand, Sony S930 has a
10.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor .
Sony S930's sensor provides 6MP more than Nikon D2Hs's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the D2Hs and S930 sensor size comparison.
As seen above, Nikon D2Hs has a 13.1x Larger sensor area than Sony S930. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.