I have the same probelm on two computers.  There are two files
apparently stuck in my Recycle bin.  I cannot empty them out, and I
cannot see them when I open the recycle bin.  Do you know why this is
happening.  Is it a threat (the computers have been acting a little
funny lately)?  Is there anything that I can do to see and empty the
files?  Please answer all questions.  Thanks!  -- Arthur

First boot into "Safe Mode".
[to get into safe mode, reboot the computer and keep tapping the F8-key.
eventually a system menu will pop up asking you what to do; select Safe Mode]

Then goto your "C:\" drive. 
At the top menu select 'Tools' then 'Folder Options'. 
Goto 'View' tab.
Under "Files and Folders" -> "Hidden files and folders"
Select "Show hidden files and folders".

Then scroll down a little and 'UNCHECK' "Hide protected operating system files".

Hit 'OK'.

Now in the "C:\" drive you should see the hidden system folder called
"RECYCLER". Inside you can select everything and delete it that should
remove anything from your Recycle Bin(s).

1.It may be caused by some recover tools. Just contact the vendor for more info.

2.It may be caused by virus. Bad luck,you have to update your Firewall
and Anti-Virus system.

Perhaps both above would make your computer acting a little funny.

Some hidden file stuck in Recycle bin is JUST the appearance. I guess
if you delete them successfully, it still will be there later because
the essential is not found.

If you see them, please post the file details like name or size here
for further diagnosis.