Please read this page. This is how to setup your computer for reading Unicode Malayalam.
For Microsoft Windows users:
If you have Windows XP with the SP2 update, you already have a working system. The Kartika font which comes with the SP2 update is a decent font.
The most likely reason why you cannot see anything on this website is that you do not have a font that supports the Malayalam Unicode range. If you can see some letters, but there are too many errors, you probably have a font with poor support for Malayalam Unicode. Perhaps the best font available is AnjaliOldlipi by Kevin & Siji. This font work almost perfectly in Windows 95/98, ME, 2000, and XP (especially with Internet Explorer 5 or over). Please download the font by following the links above and install them. To install, open “Fonts” from Control Panel.
For more Malayalam Unicode fonts, please visit Alanwood’s page .
Internet Explorer users:
If you were able to see some letters, you will need to change the font Internet Explorer uses for showing Malayalam Unicode. To do this, pull down Tools from the menubar in Internet Explorer and follow Internet Options…, click on Fonts (button). Choose Malayalam in Language script first, and choose a Unicode font (AnjaliOlpLipi, Thoolika, Rachana, Karthika etc) in the Web page font box. Restart Internet Explorer if it doesn’t work the first time around.
It seems you need to turn on “Indic” support in Windows 2000. To do this, go to Control Panel in your computer, double click on Regional Options. In General Tab, language settings for the system, check the Indic box and click OK. You may need to restart the machine after doing this. In Windows XP, go to Control Panel in your computer, double click Regional and Language Options, select Languages Tab, under supplemental language support, check the box to install files for complex script and click OK. (Can somebody please confirm this?). In case you are still not able to see Malayalam letters properly in Mozilla, you should select the font Mozilla uses for Unicode by opening from Mozilla’s menu bar Edit->Preferences->Appearance->Fonts. Choose “Fonts for:” as Unicode and all typefaces as AnjaliOldLipi.
AnjaliOldlipi works excellent on Firefox. To use it as default font to display Malayalam and Other Languages [from Tools menu > Options item > Content tab > Fonts & Colors section > Advanced button > Select “Malayalam” and set Anjali as font for serif/san-serif/monospace, do the same for Other Languages also.