I notice that installing a hosts file, which I recommend doing, seems to cause a lot of people using Win. 2000/XP problems. Mainly cause when the file exceeds 135 kb, there is a lag in system performance about every 20-25 minutes.
I prefer to use MVPS Hosts File
over "Hoster". It is updated regularly and I had less problems with it.
If you decide to try MVPS, here are the instructions to prevent the lag:
Start-->Run (type) "services.msc" (no quotes)
--> Scroll down to "DNS Client", Right-click and select: Properties
--> Click the drop-down arrow for "Startup type"
--> Select: Manual, click Apply/Ok and restart.
You can see that the above "Service" is not needed (after a little browsing) by opening the Services Editor again, scroll down to DNS Client and check the "Status" column. It should be blank, if it was needed it would show "Started" in that column.
Hope This Helps,