Disable Network Search by XP

By default, Windows XP monitors shared resources on the network to make it easier to connect to a shared resource. This feature, in Windows XP, is implemented by periodically scanning the computers on the network. During the scan, Windows XP identifies any newly-shared resources, such as a printer that has just gone online as a shared printer, or a folder that has just been shared.

If this is not needed for you, this feature can be disabled and XP will work faster.

Method 1:

Disable the automatic search for network printers and folders by changing folder options:To disable the automatic search for network printers and folders, follow these steps:
1.Double Click My Computer ,Click Tools menu ,Select Folder Options
2.Click the View tab.
3.In the Advanced Settings list, click to clear the Automatically Search for Network Folders and Printers check box.
4.Click OK.

Method 2:Disable the automatic search for network printers and folders by changing the registry key:To change the registry key to disable automatic search for network printers and folders , follow these steps:
1.Click Start, type regedit in the Start Search box, and then press ENTER.
2.Locate the following registry subkey:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
3.Right-click System, point to New, and then click DWORD Value.
4.Type NoNetCrawling, and then press ENTER.
5.Double-click NoNetCrawling.
6.In the Value data box, type 1, and then click OK.
7.Close Registry Editor.

Source: Mocrosoft Support &   http://doputtur.blogspot.com/