[Advaita-l] Pancha Mahayagna

[Sumitha Ramachandran]

Namaste,
         As a Grihini how I could improve on doing Yagna? 
Gitacharya says He is Japa Yagna of all the Yagnas. The Pancha Mahayagnas which is potent in removing sins, is explained in the shastras.
I perform Bhootha yagna by offering small portion of cooked rice with dal ghee and salt after Naivedya , to the birds , calling "haraa".
 
Today I was too sick to have a bath and cook as I had to pack lunch for my husband. After some rest , I took bath and prepared roti. I offered a portion of it to the birds. 
It is said in Shatashloki too that a person eating alone without sharing is eating sin.
Though it is preferred for the crows to cosume the food offered, here pigeons , sparrows, Myna sometimes parrots are also spotted .
 
My questions are:
 Can Roti be called as Annam during Naivedya and offered to Bhoothas ?
Is it right to shoo away a cat that searches for food remains like fish from my neighbhour Bengalis Kachhada bag kept on the doorway passage  for collection? 
 
May I please request the Respected Group to  enlighten me about all the Pancha Mahayagnas as said in our scriptures ( Sruti and Smriti )?
 
Also please give practical suggestions for Grihinis to follow Yagna which is called as Vedic Yagna for us.
 
Thanking in advance,
At His Feet,
smt.sumitha