How can I write in Hindi the credit and titles in Windows Movie Maker 2012?
Not sure but I think a hindi font could help you. Just like we use english font i.e. Georgia, Calibri, Verdana etc. to write english.
This question was previously discussed in MUO in the below link -
How can I make Hindi titles and credit with Windows Movie Maker?
I don't know Hindi, but I've just tested it with Hebrew (which is also tricky because it's written from right to left and has some contextual ligatures) and it seems to work just fine. I think all you need to do is change language (Alt+left Shift) and type away!