I also had the same problem in my Funny-book.... It has a special DATA2SD script in it which lets it to store data in the internal partition they have provided. In general companies provide a NAND of at least 100MB and it goes upto 2GB or 4 GB NAND. But funny-book doesn't have a NAND more than 54MB. Their script lets it use DATA2sd which stores all the data internally into the storage of 2GB. This script gets corrupted when a sudden restart or a sudden boot is done or happen automatically.
The only solution for it is, either if u r proficient enough then flash a new recovery(CWM preferred), and then flash either a STOCK ROM of micromax(Available on XDA). A bit of googling would do.
Else just take your receipt of purchase and go to the service center and they'd do it for u in 20 minutes.
I chose the latter method because the funny-book is of my dad and he is a bit insecure when I m with his funny-book :-D
Suggestions that it shouldn't happen again :-
1. Use advanced task killer and do not let extra task to be run in background. It helps in maintaining around 160 MB free.
2. If u r on a better level than novice than use titanium backup.(Before installing it, you'd require to download new busybox form market).
2.1 Freeze:-
1. Maps,
2. All the bloatware from micromax like elearning, entertainment, mistore etc.
3. Don't install any stuff which asks for automatic reboot(They might corrupt your DATA2SD script).
Got any doubts, feel free to ask....
If I helped I definitely prefer appreciations
. After I restart it again resets. Any help will be appreciated!! 
