MotoCache, i not sure if you tried or heard of this app, but i use it all the time and it is way easier then using ADB commands or root explorer to get to any folders that require root access. It is called droid explorer and installs on your PC. Once you have it installed all you should have to do is plug your phone in and then open the app, then it is will look like your normal windows explorer and you can get at any folder you want on your phone to push files and delete as needed. It has many other features as well, but that is what i use it for now. Works great on XP, have had issues getting it work on windows 7, have not tried it in awhile so they may have solved some of those issues now.
Droid Explorer
Just a note on this, you must have root access on your phone and busybox installed for it to work, there are instructions on how to install busybox on there website, but if you are running any custom rom it will already be installed