Rohan,
1) The BER pattern is a simple tool that gives a spatial visualization of the BER as a function of decision instant and threshold. The decision instant is the x axis generally a fraction of the bit period and the threshold is the y axis. You will also notice on the sidebar of the window that it gives a BER for the 5 different BER patterns. Basically it tells you for a given decision instant and threshold value that lie within the pattern, then you are more or less guaranteed the corresponding BER.
2) From wikipedia, http://en.wikipedia.org/wiki/Extinction_ratio you can use the highest and lowest part of the eye diagram to calculate the extinction ratio.
Let me know if this helps!