Finding a resource leak, is it the background thread or somethingelse?

My application appears to have a recourse leak. When the user starts
a background process, the handle count in Process Explorer (PE) goes
up by about 10, sometime 1 or 2 more, sometimes 1 or 2 less. When the
task is completed, there are somewhere between 4 and 7 handles still
open.

My process is loading images and shrinking them down. I went through
all the code and found some objects that implement the IDisposable
interface which I was not calling Dispose or Close on. Objects such
as AutoResetEvent, Graphic, and Image. I have either encapsulated
them in a using clause or called Dispose on the object before setting
to null and it seems to have no effect.

So I am now wondering where might I find this leak? In the unmanaged
thread handles need to be closed when no longer needed. I am not
seeing any way of cleaning up a managed thread, once it is completed.
Is there some cleanup procedure I am missing or are there other
objects out there that I am not cleaning up correctly?

Are there any good tools out there that might help me in finding this
resource leak?

Cartoper

This doesn't mean you are leaking handles, an handle leak would mean that
the handle count keeps increasing without ever going down during the
lifetime of the process, this is not what's happening here I guess, please
correct me if I'm wrong.

Also don't forget that the CLR creates it's own OS
objects, the CLR is responsible to release these handles, also don't call
GC.Collect without having a serious reason to do so.

***
Not in the menus, but on the tool bar, the sixth button is a toggle - View
Dll's/View Handles. You can also toggle using Cntrl+H/Cntrl/D
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