I have never found a way to completely secure my Windows PC but that doesn't mean that you shouldn't try. It is pretty easy to secure it from someone who knows little about computers, often the login at the start of Windows is enough.
The best way to secure my Windows box from computer savy intruders is to right-click on the desktop and go to properties. Setup a password for the screen saver of your choice. Then close that and open Internet Explorer. Locate the file that pertains to the screensaver that you used (C:/windows/system) and drag it to < C:/windows/startMenu/programs/startup >. That way, when you start windoze the screensaver will start and will ask for a password to get in.
Yes, there are ways around this. You need to see a hidden file for this so go into Windows Explorer - View - Folder Options - View and in "Hidden Files" select "Show all files". Click "ok".
Now, I go into Windows explorer and find < C:/msdos.sys > and right-click on it and go into its properties. "Read only" and "hidden" will be checked. Uncheck 'em. Click "ok" and open "msdos.sys" with a 2x right click. When asked what program to use, select Wordpad, not Notepad or any other word processor.
You will see...
[Paths]
WinDir=C:\WINDOWS
WinBootDir=C:\WINDOWS
HostWinBootDrv=C
[Options]
BootMulti=0
BootGUI=1
DoubleBuffer=1
;
;The following lines are required for compatibility with other programs.
;Do not remove them (MSDOS.SYS needs to be >1024 bytes).
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxa
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxb
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxc
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxd
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxe
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxf
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxg
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxh
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxi
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxj
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxk
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxl
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxm
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxn
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxo
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxp
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxq
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxr
;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxs
After the double buffer(actually it doesn't matter where) put in BootKeys=0 or BootDelay=0 (or both on seperate lines). Click on "File" and save the whole deal.
Your windows box is now as secure as your going to get it without third-party software. As far as I know, the only way to get in now is to reset the CMOS and to do that you have to crack open the PC and skrew around with the motherboard.
That should help if someone can physically get at your computer, but what about computer criminals attacking your computer over the internet? Well, it's mostely pretty hard to do unless a person get a trojan horse program on your system. A good virus scanner will usually pick this up (hint, hint Norton Antivirus ). A good firewall will also really help. Norton makes one but I have never used it. ZoneAlarm is a good one that is easy to setup and use.