did you open (task manager) and check what's running in the backround?
(Avast,AdAware,Defender and Spybot) all running together maybe slowing
you down more than you think. just my 2 cents
scrooge

Ensure the software was updated to their latest definitions prior scanning.
Run this also:
Malwarebytes© Corporation - Anti-Malware
http://www.malwarebytes.org/mbam/program/mbam-setup.exe

--and--

SuperAntispyware - Free
http://www.superantispyware.com/superantispywarefreevspro.html

And then:
Download and execute HiJack This! (HJT)
http://www.trendsecure.com/portal/en-US/tools/security_tools/hijackthis/download
Please, do not post HJT logs to this newsgroup.

Fora where you can get expert advice for HiJack This! (HJT) logs.

http://www.theeldergeek.com/forum/index.php?s=2e9ea4e19d3289dd877ab75a8220bff6&s
howforum=29
http://forums.whatthetech.com/HijackThis_Logs_and_Infections_Removal_f27.html
http://www.5starsupport.com/ipboard/index.php?showforum=18
http://www.bleepingcomputer.com/forums/forum22.html
http://www.spywarewarrior.com/viewforum.php?f=5
http://www.thespykiller.co.uk/index.php?board=3.0
http://castlecops.com/forum67.html

NOTE: Registration is required in any of the below fora before posting
     a HJT log and read the 'stickies' (instructions/guidelines) for
     the respective HJT forum.

Also...

Usual culprits:
1. Malware (i.e., viruses, worms, trojans, dialers, adware, spyware)
2. Failure to delete temporary files
3. Too many programs running
4. Not enough RAM (memory).

Have a look at "Slow Computer" at
http://www3.telus.net/dandemar/slowcom.htm

Pay special attention to Steps 1, 5, 9, and 13.

--and--

Help! My Computer is slow!
http://miekiemoes.blogspot.com/2008/02/help-my-computer-is-slow.html

--and-- (from Shenan Stanley)

#1: A process that's loading down your CPU:
It could be a sub-process or application that's running in the background
and taking all the CPU resources, which could be the cause of your PC
running slow.
To find and display what could be the problem try Process Explorer:
http://www.microsoft.com/technet/sysinternals/SystemInformation/ProcessExplorer.mspx

Note: Once you have Process Explorer installed and running:
In the taskbar select View and check 'Show Process Tree' and
'Show Lower Pane' options.
Then expand the process named 'Explorer' (click on the + sign) In the
column on the left named 'CPU', look for any high CPU usage. Next click on
the CPU column to sort the processes by %CPU usage (Highest to Lowest).
Move the mouse cursor over any process, you should see a popup with some
detailed info.
Then mouse over the process that's using most or all the CPU %.
Then click on that process to highlight it,
Now that  it's highlighted, right click and from the options listed select:
'Search Online'
This should display what out there on the web about that process.
You can also double click on any process to open up a more detailed
'Properties' window. Note: some entries like Explorer, System/Services, and
Svchost entries may need to be expanded to show the detail (sub processes),
in this case click on the + located to the left of the entry.

An alternate method using Process Explorer is to double click
on the Graph just below the Menu bar.
This will open the 'System Information' window, which has a larger display
of all three graphs.
Move your mouse over any spike in the CPU Usage graph to see what
process/application or service was the cause of the spike.

#2: Stuff that loads during boot or logon and then is always running in the
background:
If you want to list and explore what may be the cause then:
Try Autoruns from the MS Windows SysInternals site:
http://www.microsoft.com/technet/sysinternals/ProcessesAndThreads/Autoruns.mspx

AutoRuns will show/list all apps/etc. that load/run when you first boot
(Boot Execute tab), when you logon (Logon tab) and other programs that load
(grouped by labeled tabs) for easy viewing.
It also provides the ability to selectively allows you to stop any program
(use with care)  that you don't want to load.
You can undo any changes you have made.
Note: To get additional details on an item in the list you may need to
highlight the item (right click) and use the 'Search Online' option to get
the details, especially useful for the more obscure items in the list.

#3: Too much crap on the hard drive:
Take a look at CCleaner as a tool to remove Internet history info,
cookies, temp files, auto complete and other junk.
Note that when CCleaner is first installed most if not all the options
are checked which is far too aggressive. So I recommend unchecking
all the items listed in 'Applications' tab and in the 'Windows' tab
selectively place a check mark for only those options that are of some
value in increasing the amount of free space on your PC.

Good luck :-)

Yikes. Your problem is not half as scary as the solutions.
A lot seem to think of malware.

If your system is slow on startup, this could be a problem, but after
running all those programs, I doubt it.
I hope you're not running all of the malware programs.  If so, remove all
but your favourite two, and restart the system.
Avast covers both virus and malware.  Keep ONLY ONE virus scanner.  More
than one will cause your problem, and likely others.

Then cut down on startup programs.  Remove all of them from All
Programs->startup.

My system sped up considerably after turning off the indexing and defrag.
Searches are a bit of a pain, but the weekly defrag is just unnecessary.
Good luck!

...wait up.  Where did you get a scandisk for Vista?

Hello Pamela,

You might give these ideas a try to help improve your computers
performance.

http://www.vistax64.com/tutorials/81176-speed-up-performance-vista.html

Hope this helps,
Shawn

Pamela G;828699 Wrote:

You are comparing two computers and say one is slower than the other. Yet,
you did NOT say what CPU's are in each computer nor what speed RAM is
installed in each computer. Just because each computer has the same amount
of RAM does not make them the same. Your computer may well have a
stronger/faster CPU and have more RAM installed that runs at a faster bus
speed.

Complete specs allow others to make a more complete determination of
comparative computer speed.