Process Explorer - Find Out What Your Computer is Really Up To...

The Windows Task Manager provides a good start when you try to discover
what programs are running on your system, but it's only a first step. For
more-detailed data, you need another tool. Your best bet: Sysinternals
Process Explorer (Microsoft acquired Sysinternals last year).

Get Process Explorer for Windows v10.21 http://find.pcworld.com/56140 at
Microsoft TechNet. It needs no formal installation; just unzip it and run
the .exe file. It will then list your PC's active processes, much as Task
Manager does, but with better descriptions and organization.
Interpreting Process Explorer's information is fairly straightforward (and
killing processes works much as it does in Task Manager), but here are
some tips to help you make the most of the utility.
Consider adding the useful 'Handles' column to the view. Handles (a term
that refers to programming methodology) are a convenient way to measure a
process's resource utilization. Processes with high handle usage should be
the first ones you kill when resources run low. Add the column by
right-clicking in the header area and clicking the Select Columns option.
Click the Process Performance tab and check the box next to Handle Count.
Note that Handles can also be created for media-based devices like CD-R
drives, which may cause errors on eject. If you can't safely eject a disk
or memory card, use the Find menu to search for the drive letter followed
by a colon (for example, E:), and kill that process directly.
Instead of outright killing a process, you can suspend it (right-click on
a process to see this option). This can be useful in the case of a runaway
program stuck in an endless loop.
Want to know what a program's process identification is to better tell
whether it's friend or foe? Open the program, then switch to Process
Explorer. In the top-right corner is a target icon (concentric circles).
Click this icon and drag it onto the program you want to ID; Process
Explorer will highlight the process.
http://www.microsoft.com/technet /sysinternals/SystemInformation/ProcessExplorer.mspx