I wish to enable data transfer between two PCs using "USB cable with both ends having standard type A plug", is it possible to do so? What will be power related issues n use of power pins as both computers run with own power?

You will need a special USB cable like this one from Belkin USB to USB file transfer cable.
Your current cable will not work as USB which is known as a 'dumb' technology it needs a controller chip of some sort to connect the two devices for a file transfer.
Consider if you had FireWire which is known as a 'Smart' technology does not require a controller chip to make the connection between the two devices. The other consideration would be a Cat5 cable and connecting each computer and transferring files over the Ethernet connection.

No USB has to have a controller chip in between.

Thanks for ur reply, I'm aware of such cables...."Belkin USB to USB file transfer cable" but can't be this controller be put as a software in the PCs itself??? I wish to have the cable with two USB ends with no bridging in between. Looking forward for ur reply.