Hi,
I need more insight to what my (win XP) PC is doing.  Frequently it
begins running really slow and i do not know the cause.  Task manager
shows CPU% and memory to be OK. Running perfmon could tell me what was
hogging the system if i knew which parameter to inspect.

The ideal tool would be able to monitor everything and tell me what is
"out of order" when i ask it.

For example the tool may report that the hard disk is being accessed
much more than usual, or that the network interface is overly active.

Answer criteria:
1.  Link to tool, which must offer with demo version.
2.  Cost of tool can not be over $40

Thanks!
Steve

Do you require to have a tool that does it all for you?  I tend to use
sysinternal tools, and they help me notice things such as intrussions,
memory hogs, excessive registry activity under an unknown
applications, large amount of tcp connections, and all this combined
sometimes with Network Sniffer - since many times your system can be
slowing down due to DOS (spyware, adware, games, large variety of
applications installed - Windows Apps tend to have this problem, where
the more apps you install the higher the chance for losing
performance).  You should also look into Anti-Spyware software, anti
virus, and a decent firewall (since, these tend to alert you about
network access per process)

You may also want to determine that your problems are not harware related.

Hi,
Thank you for the comment.  Is sysinternals from 
http://www.sysinternals.com/?  I will check it out.  I would like a
tool that auto-magically would tell me everything.  But, i would be
happy enough with a tool that makes it easy to find out what is
bogging down my PC.  This tool probably would not cover *everything*,
but hopefully would help me spot a large number of items.

A current problem is that a NT machine begins running real slow, to
the extreme that it can not keep up with my humble 40 words per
minute.  The task monitor shows that the CPU % is OK.  I have good
antivirus software, last spyware sweep seemed good, i have not
installed new stuff in ages.

A couple examples of problems that were difficult for me to find (and
the hope that easer tools would save me time):

1.  WinXP and Zip Files.  WinXP can browse zip files when running file
explorer.  If you have several large zip files at C:\dir\ then the
windows explorer will really run slow when  clicking the c:\dir\
folder. This is because windows kind of opens the zip file when you
click the folder (just in case you wish to preview the zip file). 
This problem would have been spotted by noticing disk access and CPU
usage.

2.  WinXP trash can:  WinXP trash can has an allocated size.  If
deleted files exceed this size then the system will run really slow
when you delete new files (even tiny text files).  I guess windows is
compressing the trash can.  Again the only real key here would have
been CPU and disk access.

Thank you for your time,
Steve

Hi uoy_pleh_i_yam_woh-ga,
I like the sysinternal tools!  The registry watcher showed massive
activity from  a TV-tuner card (kept registering that it got a packet
- but nothing was plugged into it).

Please copy/paste your comment as an answer.
Thanks,
Steve