use a flashdisk to transfer some big files off the hdd, use disk clean up tool from windows or use a cleaner software like piriform's ccleaner, defrag, put the files back in. you can disable your page file and hibernation file to free up more space and defrag the spce both files occupy.
you can use alternative defragging softwares like piriform's defraggler. iirc defraggler lets you defrag individual files.(imo both ccleaner and defraggler both are good at what they do)