You can try this:
open a command prompt. Type:, without the quotes, "Chkdsk c: /f". You will get a message saying that CHKDSK can't run, do you want to run CHKDSK on the next reboot. Press the "Y" key. Reboot. CHKDSK will then check and fix any disk errors it encounters. After the computer reboots, run defrag. Then run your cleanup program. How much free space do you have? You may need to delete .bak, .log, .tmp files. Do a search for them and delete them as you find these files (Or use a program such as System Mechanic, etc.)