Left mouse click not completed in timely manner

I am running 10.4 which was upgraded directly from an up-to-date 8.04. This problem did not exist in 8.04.

When selecting anything that requires a single mouse click (item from drop down menu; icon in panel; button in dialog; etc.)
the response -may- be delayed (for some considerable time, as much as 9 seconds). During this delay, any mouse action
such as a mouse move will cause the action to be performed. As a secondary issue, and I believe these two are related,
when scrolling vertically in a window using the mouse, sometimes the single mouse click is processed as a double click (that
is, instead of scrolling one page, two pages are scrolled).

To aid you in finding this bug, I have done some additional testing which I will describe below. But first,

I have a Logitech keyboard/mouse combination (MX 3200) which is wireless and USB connected. I have borrowed a
keyboard/mouse combination (same make and model) that works fine on a Windows system, and I get the same type problem
on my system with that mouse. In addition, my mouse works fine on the Windows system.

Now for my testing. I have modified the program 'xev' to add an output line to the ButtonRelease data. It can be identified as
'diff xxxx <<<<' where xxxx is the time between when xev receives the ButtonPress event and the ButtonRelease event, in
milliseconds. Here is an example of the output from the modified xev program.
---------------------------------------------------------------------
ButtonPress event, serial 30, synthetic NO, window 0x4000001,
    root 0x117, subw 0x0, time 19405714, (132,33), root:(312,573),
    state 0x10, button 1, same_screen YES

ButtonRelease event, serial 30, synthetic NO, window 0x4000001,
    root 0x117, subw 0x0, time 19405848, (132,33), root:(312,573),
    state 0x110, button 1, same_screen YES
    diff 177 <<<<

ButtonPress event, serial 30, synthetic NO, window 0x4000001,
    root 0x117, subw 0x0, time 19407234, (132,33), root:(312,573),
    state 0x10, button 1, same_screen YES

ButtonRelease event, serial 30, synthetic NO, window 0x4000001,
    root 0x117, subw 0x0, time 19407384, (132,33), root:(312,573),
    state 0x110, button 1, same_screen YES
    diff 149 <<<<

ButtonPress event, serial 30, synthetic NO, window 0x4000001,
    root 0x117, subw 0x0, time 19408738, (132,33), root:(312,573),
    state 0x10, button 1, same_screen YES

ButtonRelease event, serial 30, synthetic NO, window 0x4000001,
    root 0x117, subw 0x0, time 19408856, (132,33), root:(312,573),
    state 0x110, button 1, same_screen YES
    diff 2269 <<<<

MotionNotify event, serial 30, synthetic NO, window 0x4000001,
    root 0x117, subw 0x0, time 19411008, (132,34), root:(312,574),
    state 0x10, is_hint 0, same_screen YES

MotionNotify event, serial 30, synthetic NO, window 0x4000001,
    root 0x117, subw 0x0, time 19411064, (132,35), root:(312,575),
    state 0x10, is_hint 0, same_screen YES
---------------------------------------------------------------------
In the first two ButtonPress/Release events, the difference in the event times as reported in the output is consistent with the
time difference that xev sees (177 milliseconds and 149 milliseconds).

But in the third ButtonPress/Release event, while the difference in the event times as reported in the output (118 milliseconds)
is consistent with the other two, xev didn't see the ButtonRelease data for 2269 milliseconds, and then only because I moved
the mouse.

To me, this would indicate that the release of the mouse button is seen by the system when it happens, but for some reason, it
is not reported back when asked for. Also, if I had not moved the mouse, after some varying amount of time, the ButtonRelease
would have been given to xev, as if something was awakened by a timer expiring.

Also note that if some other application that consumes some significant amount of system resources (such as System Monitor/
Resources) is running, this problem does not occur (or at least with the testing I did).

While I am not a linux guru, I will be glad to provide other information, if you tell me how to get it.

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: linux-image-2.6.32-23-generic 2.6.32-23.37
Regression: Yes
Reproducible: Yes
ProcVersionSignature: Ubuntu 2.6.32-23.37-generic 2.6.32.15+drm33.5
Uname: Linux 2.6.32-23-generic i686
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.21.
Architecture: i386
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: olsenra 1766 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'Intel'/'HDA Intel at 0xe0320000 irq 22'
   Mixer name : 'Realtek ALC1200'
   Components : 'HDA:10ec0888,8086d701,00100101'
   Controls : 28
   Simple ctrls : 17
Date: Sat Jul 10 13:38:46 2010
HibernationDevice: RESUME=UUID=292f401c-1fe1-46cf-830e-12a665fd852b
IwConfig:
 lo no wireless extensions.

 eth0 no wireless extensions.
ProcCmdLine: root=UUID=aa6d7c27-2607-4b55-9d27-c42c8f806e6f ro quiet splash
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
RelatedPackageVersions: linux-firmware 1.34.1
RfKill:

SourcePackage: linux
WifiSyslog:

dmi.bios.date: 02/03/2009
dmi.bios.vendor: Intel Corp.
dmi.bios.version: ECG3510M.86A.0112.2009.0203.1136
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: DG35EC
dmi.board.vendor: Intel Corporation
dmi.board.version: AAE29266-209
dmi.chassis.type: 3
dmi.modalias: dmi:bvnIntelCorp.:bvrECG3510M.86A.0112.2009.0203.1136:bd02/03/2009:svn:pn:pvr:rvnIntelCorporation:rnDG35EC:rvrAAE29266-209:cvn:ct3:cvr: