|Your question doesn't make sense.|
If your free disk space is less than 15% you risk trashing the entire operating system and losing all your data.
You need to delete un-needed data and old files.
You may not be able to delete using recycle bin in view of low space. Suggest you use CTRL/DEL which bypasses recycle bin but be careful not to delete system files.
Uninstall unused programs. Copy images/music/movies to CD/DVD to free up more disk space.
You have not given any information on the actual size of the disk That might be useful.
Have you run disk cleanup?
Consider buying another larger harddrive to use as additional storage.
Goin' Fishin' (Some day)