Problems with Trash

First off, I have a midrange white macbook (prissy). onward..

Well, I was looking in the "all documents folder" and silly me, I tried to delete something I didn`t want on my computer anymore. When it was successfully dragged to the trash, I tried to empty it, but I kept getting the error message "The item .Trash is in use right now and cannot be opened. Try again when the current task is complete" SO i`ve tried pressing both stop and complete, and I keep getting the same result. Now I have files in my trash that I can`t drag BACK to the all documents folder, or get rid of. Help please?

Also, how do I delete junk that`s already been erased from my computer from the all documents folder..?

Thanks a bajillion.