The FIRST thing you need is anti-virus, and
make sure it is configured to download the latest updates at least once a
week.
www.grisoft.com is free anti-virus, use it. [Note that once you are
infected, your anti-virus may not be able to remove some viruses, in which
case you have to download and run the
www.mcafee.com "Stinger" tool or
search the virus encyclopedia on the web site of your anti-virus
manufacturer for the exact name of the virus found on your computer, in
order to download a special one-time virus removal tool.]
If you aren't running XP, you need to get your own firewall.
www.kerio.com,
www.sygate.com and
www.zonealarm.com are all free firewalls. Get one.
The LSASS vulnerability is fixed by the MS04-011 patch. You need all the
Microsoft patches, but pay special attention to that one. First, download
and install that patch by going to
www.microsoft.com/technet/security and
reboot. Then, be sure to visit
http://windowsupdate.microsoft.com about
once a month [preferably Wednesday after the second Tuesday of every month]
to get all the patches you need. The first time you visit there, you may
have to visit the site and reboot two or three times in a row to get all the
patches.