Go to windowsupdate and download the Arabic text support (or alternatively go to an arabic website where the charset is properly set and you should be prompted to download, such as
http://www.aljazeera.net. Then you can get Arabic to display by selecting Arabic as the encoding (this is necessary if the charset is set to ISO-9660 or whatever and there is some arabic text, such as this post - the page is set to an english charset but I had to post my arabic in an arabic charset, so you have to manually change the charset to view it. On a page that's fully arabic, you would have a line in the HTML file that said <META content="text/html; charset=windows-1256" http-equiv=Content-Type>. Anyhow, to manually change charset for a page, in IE it's view, encoding, your charset.