Why we pray Lord Vinayakar first ?

Yes, this Question arise in our mind frequently.
The answer is when lord vinayakar(ganesha) get this Elephant head and human body,that time her mother Parvathi devi was Crying a lot because of his son is like this... how he may be in future like that.... then at that time Lord Siva said ok "Hereafter our son will give darshan first when everyone come to pray/to darshan me"
yah this the reason that we pray lord vinayakar first when we go to the temple
while when we pray lord Vinayakar mostly people will pull the ear and they kneel up and down- The reason behind this is there is connection between the nerves of ear and brain ,body..... when we pull ear that time a energy direct towards a refreshment for us and a slight activation takes place (we may know olden times teachers will just touch the ear when any student doesn't do the work properly )Kneeling may be exercise for us that followed from the olden days .Just i shared what i heared.
To know more see this following link:
http://rapidshare.de/files/47966680/Vinayaga.exe.html