Depends on the Video Card you have. Usually the best place to start is with Toshiba directly, not sure how good they are here, but in Vista to figure out what you got, do this Right click on the desktop > Personalize > Display Settings > Advanced Settings > Properties, then you be able to see something. My Lenovo, has a Intel Graphics Accelerator tab that you can use to adjust the graphics.
Some other options, try using Internet Explorer and check in Firefox under options, make sure you have both the Java sections enabled.
Also have you been able to view videos on YouTube or anywhere else?