If you feel that it is not the screensaver (i.e., all screensavers do the same, or this screensaver is much more detailed and/or animated), then the only things I can think of are:
1 - Go to the Toshiba web site and see if they have any updated drivers for the model Intel Graphics controller your machine is listing. In general, you will always want to go to the manufacturers web site first to download graphic controller drivers (or verify that you can download from the graphic controller manufacturers web site) when working with a laptop. They are often specialized drivers, and obtaining them from say Intel directly may or may not work correctly.
Note - Intel is currently offering an updated driver for your graphics controller, which was released on September 28, 2005, and can be downloaded here http://downloadfinder.intel.com/scripts-df-external/filter_results.aspx?strTypes=all&ProductID=922&OSFullName=Windows - you would want download #1.
Please verify with Toshiba whether or not you can use this driver before installing. It is listed in Intel's "Laptop Graphics Controller" section, but it is always best to be sure before installing.
Intel does indicate the 82852/82855 GM/GME Graphics Controller to be compatible with, and support the OpenGL 1.3 specification. It also indicates a 32 MB memory, which is not a whole lot of memory resources - but should work with many screensavers and basic games.
2 - Try changing the settings on the screensaver (i.e., the animation speed if available). If you slow the speed down and there is significant improvement, then you are probably experiencing the limitations of the graphic controller's 3D capabilities, or memory resources.
3 - You can try changing the hardware acceleration settings via "Right-click desktop > Properties > Settings tab > Advanced button > Troubleshoot tab > Acceleration slider". This may actually increase the issue, but may be worth a shot.
Again, if you are experiencing a "global" issue (all screensavers) in performance, it would point to a limited graphic controller. If on the other hand, you see issues with less than say 20% of your screensavers, then it is more likely that the screensaver was made for higher end graphics cards/adapters - or is faulty in some way.
I hope this helps.