You should include what version of Windows Vista you are using and how much
RAM you have on your computer.

Windows Defender is not an antivirus program, but an anti-spyware programand
pop-up protector.  You do not need to keep it ON if you do not want to.  AVG
may provide anti-spyware, adware and other such protections.  This is what
Defender does.

Windows Defender is a free program that helps protect your computer against
pop-ups, slow performance, and security threats caused by spyware and other
unwanted software. It features Real-Time Protection, a monitoring system that
recommends actions against spyware when it's detected and minimizes
interruptions and helps you stay productive. Now with 2 free support
incidents for Windows XP and Windows Server 2003.

The program and updates should not beoverloaing your computer memory or make
your computer run slower.

You have to keep it but you don't have to let it run.

You can disable it by going into

Control Panel (Classic View)

Administrative Tools

Services

Find Windows Defender and disable it, then stop it.

No you can disable and stop it as described by others. However, if you do
you will probably be back later asking how you can clean up your system.
Much easier to keep it clean.

1) It is not necessary to use Windows Defender in Vista.
2) Windows Defender may be uninstalled, if you wish.
3) DON'T USE IT, anyway.  
I like to call it "Windows STOPPER", rather than "Windows Defender",
since it seems to stop more legitimate programs from running than
illegitimate ones.
3) The Updates do require a minimum amount of free ram to run.
4) The only way your "RAM" could get "overloaded" is if your system
simply doen't have enough RAM to use Windows Update.
5) Your computer will definitely slow down if you don't have enough
Disk space, or if your computer hasn't got adequate RAM to run
effortlessly.

6) If you mean "will the updates from Microsoft, once installed,
overload your memory, the answer is "NO", since if there is not enough
physical RAM to accomplish the task at hand, Windows will page memory
to disk (i.e., "Virtual memory").
7) Memory paging to disk WILL slow your computer down, since it will
take longer to access the data which has been paged to disk, physical
memory access being much faster than disk access.

Vista wants as MUCH PHYSICAL MEMORY as your machine can handle.
I advise you to "max-out" your memory slots (use the largest, fastest
memory sticks your motherboard is able to use.)

Also, when using Windows Update, ALWAYS disable ALL anti-malware
programs until the updates are installed (even if you have to
uninstall your Anti-virus program, and reinstall it once the updates
are installed).  Not all AV programs may be temporarily unloaded from
memory, so such programs will have to be uninstalled while using
Windows Update.

Additionally, while you can do it, I do not advise running any other
programs while using Windows Update, so make sure they are not loaded
and running during that time.

Donald L McDaniel
Please reply to the original newsgroup and thread.
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