If your computer is connected to a domain, Parental Controls are not available.
You can use Parental Controls to specify which websites your children can and can't visit. You can also block some websites based on the content they contain.
Open Parental Controls by clicking the Start button , clicking Control Panel, and then, under User Accounts, clicking Set up Parental Controls.
If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
Click the account that you want to set up the web filter for.
Under Parental Controls, click On.
Click Windows Vista Web Filter.
Click Block some websites or content.
Click Edit the Allow and block list.
In the Website address box, type the address for the website you want to allow or block, and then click Allow or Block.
Turning on the web filter should significantly reduce the number of websites your children might view that contain content you have decided is objectionable. However, objectionable content is subjective, and the filter might not block all of the content that you want it to block. Also, because new webpages are published all the time, it takes time for the filter to analyze and rate the content.
Under Block web content automatically, click the content level you want.
You can prevent file downloads by selecting the Block file downloads check box.
Parental Controls filters websites for adult content (including pornography) in the following languages: English, French, Spanish, Portuguese (Portugal and Brazil), German, Dutch, Chinese (Simplified and Traditional), and Japanese. Parental Controls filters only for pornography in the following languages: Norwegian, Danish, Swedish, Finnish, Italian, and Korean.