Greetings,
If you want to reduce the amount of disk space the cache files are taking up on your disk, go into the Program Preferences and set accordingly. Since you didn't mention the program to which you are referring, I can't give you exact instructions. But regardless, it should be in the preferences/options.
You can set the Disk Cache to the size most appropriate for your use. Usually, five megabytes (enter a value of 5000) is a good size to set it to, although you may want to set itas small as 2000 or as high as 10000. You can also press the "Clear Disk Cache Now" button (with many programs) to completely empty out your cache.
Internet Explorer, for example, the following applies:
On the Tools menu in Internet Explorer, click Internet Options.
On the General tab, click Settings.
To create more space to store pages temporarily, move the slider to the right.
To define less space to store pages temporarily, move the slider to the left.
Good luck,
Maxwell