Received a compliance email from income tax dept

I received a compliance email couple of days ago from IT Dept. My returns for A.Y. 2010-11, 2011-12 were not filed and moreover these are time barred now. Actually I missed them unwillingly, just because I forgot them to do, I admit this was my negligence since I was under impression that when TDS were deducted by employer, then what was the sheer need to file the returns. My mistake !! 

Now I am pretty much worried as to what will happen and how can I file these time barred returns? 

In eFiling website, my 'Related Information Summary' tab only asking about TDS information (TDS-92B) for F.Y. 2009-10 and 2010-11. My TDS and Tax Credit 26AS matches perfectly for the respective AY years 

If someone can very kindly guide me in:- 

1. What I should select in the "Response" and "Reason" under 'Filing of Income Tax Return' tab in "Submit 
Compliance Form" 
2. What in the 'My 'Related Information Summary' tab in "Submit Compliance Form" 
3. How to file these time barred returns? 
4. Is there any penalty to be incurred? 
5. How and who to approach in Local IT office? 
6. What documents are needed to file them? 

Awaiting reply.....Thanks so much in advance...