Auto Correct is very useful tool that will change the wrong spellings like "adn" to "and" as soon as you type. This is a marathi autocorrect file that should be copied to
C:\Documents and Settings\UserName\Application Data\OpenOffice.org\3\user\autocorr
If the folder is not visible, try ... Tools - Folder Options - View - Show hidden files and folders
Make sure that open office detect the language as "Hindi" on the status bar.