Some systems come with just the setup files for these programs, and you can safely just delete those. Other systems may have these programs already set up. If you don't have and don't wish to purchase an uninstaller program, you can at least delete those folders and pick up that much space. You can safely delete every avi file from your hard drive as well as most wav's. You are probably only using a few wav files as your default windows sounds.
Clip art is another big space waster for many people.
Delete all those. Another thing that many people don't realize is that every file, no matter how small, takes up the minimum cluster size on your system. If you have a lot of data files you want to keep but don't use much, consider archiving them in ZIP files. Using the free downloadable trial version of WinZip , you can effortlessly drag lots of files into a few zip files. You can then delete the original files and just extract them when you need them.