This Article is oriented to home users with internet access through local area network (LAN). We will make Windows more secure, will forbid danger services and protocols, will set up and tweak security options. Also we will filter every opened ports and will stop unneeded features offered by Windows and not so safe about network security. When we finish with this your PC will become a fortress. But here someone will say that every firewall program can protect the system, even we don't have to making any set ups, any modification of the system. This is true. The firewall will protect you from outside attacks and will stealth the opened ports, but we will secure your Windows on higher level and even without firewall, the ports will be closed and most of features for remote access (most of this are implemented like services and protocols) will be stopped.

Windows Update
If you still have Windows without any updates ia better to do this immediately. Download the latest service pack for your Windows and install it.

Close all opened ports
The communication between remote computers connected in your LAN or within Internet realized by this ports. Think for this ports like small doors. Each port have a number and most important ports have names.

Stop the Guest Account
This is a special, system account, which cant be deleted or changed. You can only disable this account.

Change the port of Remote Desktop.
If your Windows wasn't updated soon someone can easy exploit this service and take remote control of your computer without any limitation.

Stop NetBIOS
In most networks NetBIOS is not used and you can stop it. If after this your internet connection was droped, just turn it on back.

Stop sharing
Like all we know, Windows offer features for sharing folders and drivers. But this is to risky, especially the administrative shared in professional, corporate and server versions of Widnows. This shares provide access for administration of the system, but can be used for unauthorized access or from viruses and trojan horses.

Protect from Buffer overflow attacks
If you have Windows XP with SP2, you can stop this kind of attacks by software method. I say "software", because also have a hardware method.

Install Anti-virus and firewall programs
If you already don't have it - the moment was come. After all of this lets finally close the potential danger hacker doors. Choose some popular and proved anti-virus and firewall software and install both. Also you have to know that most often updating of this software programs will give you better protection.

Conclusion
Now, if someone want to hack your system, first he have to discredit the firewall (i suppose you don't have firewall and now you will install) and next he have to find some security hole in the system. This will be more hard for the hacker if you do all described in this article about improving security of your system.