[F3L0N]

First post, please be gentle. (Windows 7 Home) I've upgraded to an SSD for start-up drive and for primary programs and the like... Now I have a 1.5TB HDD in the second slot which I want to free up some room on by removing all the old Windows OS files... I apologize if this has been addressed already but I've looked everywhere and haven't been able to find a solution yet(at least none that have worked for me). I've got about 21GB of space on the old drive being taken up by the Windows folder, which I am trying to delete. I've changed ownership several times (between Adminstrators and my user name) and tried to delete this folder to no avail; I keep getting the "you require permission from User-PC/User--or admin name--to make changes to this folder". I've manually changed permissions and used the "takeown" registry application, but I am still not allowed to delete the folder. I was able to go into the Windows folder and delete a lot of the individual folders contained therein, but I'm still left just over 17GB of main system files. Does anyone have any insight regarding how to get rid of these files? I was able to get rid of the previous back-up partition with little issue, but the rest of the old Windows install is really giving me trouble... TIA for any help!
-F3L0N