Can't Delete Previous Systems Folder

Question

I did an archive and reinstall some time ago, and got what I needed from the Previous Systems folder. So I tried to delete it (Secure Delete), and got most of it gone. What is left is a "Previous Systems" folder, with an "Previous System 1" folder inside, which shows up in the window as empty. When I try and delete it, I get a message that I can't because "html" is in use. I went in via Terminal, and found a series of directories under my "empty" Previous System 1:
usr/X11R6/lib/X11/doc/html, with a ton of ".html" files in the "html" folder. I got rid of all those files, then tried to get rid of "html", but it tells me that it isn't empty. I used sudo rmdir, and sudo rm -rf, and I get the same message. What gives, and what can I do about it?

Answer 1

Just to follow up on my problem, I finally had to backup my drive onto another drive, reformat the disk, and copy everything back. The unempty-able Trash was then empty. I still have one other problem that I hoped all that would fix, but I'll post it as a separate question. Just in case someone's curious, the problem (which I had before) is that sometimes upon waking from sleep, I get no response from the machine in that:
1.) The battery/power meter doesn't update.
2.) Once I try and click the cursor on anything on the screen (Locations, a window, the Airport menu bar), I get a spinning beachball that goes on for minutes. When it goes away, I try clicking again, and back it comes. Eventually, the machine "catches up" and works, but it's very inconvenient. Usually, this happens after the machine has slept over night. It could be a network issue (i.e., it's looking for the network it saw the night before), but it doesn't happen everytime. It's enough to make me wonder why I bought a Mac.