1) Yes a 30 points gain will help your cause because the applicant pool you are competing with is the IT crowd who generally has a very high GMAT average score. But the amount of effort you will now spend for gaining these would be very costly because many major B-school deadlines are near. So now 680 being a decent score at your work experience and not an awesome one, you still should concentrate only on writing some brilliant essays. All your leadership and cost projects should find a detail but impactful mention in your essays. Here is a brief blog that will give you some writing capital for your essays:

https://ivyctorofficial.blogspot.in/2012 ... ssion.html

2) You will have some parameters you should consider for school selection:

a) Placement statistics of school: Look at the employment report for how many people got jobs in various functions in Technology sector.

b) recruiter lists: Look at recruiter lists. All this info is available on B-school sites.

c) Geographic location of colleges: Stanford, Georgia Tech are B-schools that are located near technology hubs and hence a lot of tech companies visit their campuses or if you scout out you will have a lot of avenues to look for a tech job.

d) What is the B-school known for: Does is have a good Tech MBA program. A lot of this knowledge may be subjective views expressed by various experts on different internet forums. But if a lot of experts say that UCLA or Kelley are known for a tech program, you better research them.

If you have any other questions, do let me know.

Thanks a lot Ivyctor2010 !!!
Your response is very insightful and helpful. I will go through the points mentioned by you.
I am very much sure that I will get more doubts, will get back to you again with more questions

Always happy to help my friend. Best of luck!!