Do you know what video card you have?
If you are running Windows 9x, then right click on "My Computer" and go to properties. Go to the device manager (check the tabs on the top) and look for "Graphics Adapters" or "Display Adapters" or something like that. It should then tell you what video card you are using.
From there you have 2 options... you can either post the name of the card here and someone will be able to tell you if it is full openGL or not... OR you can go to the web site of the manufacturer of your card and see if it is openGL compliant. BTW, while you are there, you should download and install the latest drivers for the video card. There should be instructions on how to do it on the website.