Deleting stuff from the d-drive (I assume that's a hard disk also, not a CD or DVD or USB-stick) is just the same as deleting from the c:-drive. Use the delete-key in My Computer or Windows Explorer or choose 'delete' from the right click menu.
Speed of the system generally is not related to how full the disk is. If it is, it must have other causes.
Not too computer saavy about drives.
My C drive which I always use is getting full, so I am going thru and deleting, etc.
but just hit "properties" on my D drive and it is almost full too....how do I delete that stuff........
my system is rather slow, that is why I started looking into this.