FujiFilm S2500HD has a
12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Samsung WB150F has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor .
Below you can see the S2500HD and WB150F sensor size comparison.
FujiFilm S2500HD and Samsung WB150F have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since FujiFilm S2500HD has 32% larger pixel area compared to Samsung WB150F, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.