you dont realy need a special software for your scanner. you just need to install its driver. windows xp have a program that you can scan your picture.
Check its installation. Reinstall it if it does not work. I am also using Canon Lide 20, I never had this kind of problem.
All you have to do is go to and then go to drivers nd softeware pick your model scanner from a listr, download the driver and software plug in your scanner nd restart computer then you will have a tool bar from canon and which has a big button saying...