Laptops do not have replaceable graphics cards. They have on board chipsets.
Your best bet is to use a good registry repair product (such as PCTOOLS Registry Mechanic), there other great products also. Vista and Windows 7 are both prone to registry errors. Also keep your drivers up to date. These to issues are the most common problems on any PC. "Driver Genious" is a great product to keep your drivers up to date. There are other very good driver update programs.
You can also make more memory available for graphics applications. If your laptop is using a NVIDIA Chip set you can use the NVIDIA TurboCache Utility to do this. The other option is to go into your BIOS setup and assign some of you system RAM to be used by your graphics. Unless you are using very high end Games or other Graphics apps, make sure you have no less than 512MB assigned for graphics. If you have 3GB RAM or more system RAM, you will not see a drop in system performance.
Some laptops can have their cards upgraded, but the options are limited to what other laptops of the same series had installed. I have upgraded cards in G55's (Nvidia 9200M GS to 9600m GT), X205's (8700M to dual 8600M GT Sli) and an X305 (9800M GTS to 9800GTX). I am currently rebuilding the X305 and it will soon have Dual 9800M GTS Sli graphics. This upgrade requires swapping over to the Nvidia chipset motherboard used in some X305's as the socket the dual GPU graphics card plugs into is different than the socket on the single GPU cards used on the intel chipset boards. Thank god for ebay...
Your unit has intel graphics installed and that can never be upgraded as the chip for that is part of the motherboard. (intergrated graphics)
How to upgrade X205's http://forums.toshiba.com/t5/Satellite-Laptops-all-other/info-for-X205-owners-about-overheating-and-upgrading-hardware/m-p/71871 How to upgrade G55's http://forums.toshiba.com/t5/Qosmio-Laptops/Upgrading-Qosmio-G55-q804/m-p/73304 Coming soon: How to upgrade X305's