Deposit of carried over income in cash

I am a fifty nine years old lady living with my husband and son both earning and taking care of all house hold expenses. All of us are IT assesees with no tax liability since our income is below the limit. I personally own a house which I have let out for a rent of Rs.Thirty thousand per month and keep the rent received in cash for the past two years in my house, amounting to Rs.Seven lakhs in old denomination. I avoided depositing this amount in the bank for some personal reasons. I have declared this income in my IT returns for the past two years. At present out of the seven lakhs I have converted two lakhs into new notes. I can also change the remaining old notes into new notes through my relatives. My question is: Is it mandatory to deposit all my money into my bank account ? How much amount will the IT dept.accept as carried over income ? How much amount can I deposit above Rs.2.5 lacs in the bank now ? How much of cash can I retain with me in my house ? Is it compulsory to spend my money on my family expenses for IT purpose?