Please note that when you first run Picasa, it will display in the same language as your operating system. You can change Picasa settings at any time, however, so that it displays in your desired language. To do so, please follow these steps:
1. Open Picasa
2. Click "Tools" at the top of the page. This is the second option from the right.
3. Select "Options" from the drop-down menu.
4. Select the "General" tab, if it's not already selected.
5. Select the language you wish to use from the "Language used in menus and dialogs" drop-down menu.
6. Click "OK."
You will need to close and re-open Picasa to display the new language.
Finally, please keep in mind that Picasa is currently available in the following languages: Bulgarian, Catalan, Chinese (Simplified), Chinese (Traditional), Croatian, Czech, Danish, Dutch, English (UK), English (US), Estonian, Finnish, French, German, Greek, Hungarian, Icelandic, Indonesian, Italian, Japanese, Korean, Latvian, Lithuanian, Norwegian, Polish, Portuguese (Brazil), Romanian, Russian, Serbian, Slovak, Slovenian, Spanish, Swedish, Tagalog, Thai, Turkish, Ukrainian, and Vietnamese.