Phenom Processors have L3 cache which is missing from the Athlon X4's . Cache comes in handy while gaming and number crunching i guess. and for ur usage pattern, the AthlonII X4 is fine. So you can save some money.
For motherboard, If gigabyte is not available, these are the options in the order of preference :
MSI 785G E53 -- 5600/-
MSI 790GX-G65 -- 7000/-
Asus 785TD-V-EVO -- 6800/-
The last two bords support crossfire, so if you are not planning to use more than 1 GPU, MSI 785G-E53 is fine for your needs.