The CS Subjects :
First select in which area you want to learn. There are many streams in MS in CS. Few being :
Artificial Intelligence
Introduction to NLP
Machine Translation & Information Extraction
Multi Agent Systems
Speech Processing
Distributed DBMS
Web Data & Knowledge Management
Data Warehousing & Data Mining
Advanced Database Systems
Digital Image Processing
Computer Graphics
Computer Vision
Multimedia Systems
Pattern Recognition
Advanced Signal & Image Processing
Soft Computing
Machine Learning
Advanced Computer Graphics
Cryptography and Network Security
Performance Evaluation of Computer Systems
Principles of Programming Languages
Programming Language Processors
Computer Architecture
Numerical Methods
Theory of Computation
Advanced Algorithms
Spatial Databases
[I copy pasted

]
These are just examples to get you started. There are still many ! Now you might know about these Or may not. Just simply visit MIT Courseware Or Coursera & join the courses which you feel interested. Within a month you will find out what you want to study [even if that decision goes wrong, later you can change again]
US of A :
Cracking GRE is very easy, but getting into USA & getting into good univs is very tough. I don't want to discourage you, but since 2010, they are rejecting visas very much. They are just looking for a reason to reject :-/ In Visa interview process if they somehow assume you are going to stay in USA forever, then gonna stamp you as Potential Immigrant 214B & reject your Visa. And you will be asked about this next time again, when you re-apply for Visa.
However, if you can make it to any top univs then it visa will be very easy.
Top Univs :
There are many good universities in USA. But remember GRE score does not entirely contribute to admission process. First & foremost weightage will be given to Research Experience in the area of field you want to study. If you have worked under any renowned professor / published any papers, then it will be useful. Or internships at companies like Microsoft or IITs. Secondly, they consider your academics. Since you are 8+ pointer, I guess it's good. Then LOR from professors you worked / studied under. Even SOP & extra curricular activities / prizes etc.
What I am trying to say is, you need to have good ~ balanced profile. A 330+ GRE score alone cannot land you in a top 5 univs.
TA / RA :
This even tougher to get :-/ But however once you decide your univ & stream, contact the respective professor. mail them & try to impress them. This will help you alot.
If no TA/RA...
Since you are good in programming languages, you can make use of that knowledge to earn money. A friend of mine has become part time web developer & earns decently. Apart from that there will be campus jobs too. But still education in USA is costly & you cannot completely rely on your earnings to pay tuition fees [though that depends]. But in countries like Canada education is cheaper & you can save money & pay tuition fees.
Funding / Scholarships / Tuition Fees :
Getting a scholarship nowadays is almost impossible :-/ Tuition fee varies from university to university, if you get into top univ then expect fee around 40lakhs INR/2 years to 1 crore. Again, this could vary. So you have to rely on loan OR own funding. However, according to a friend of mine, you could earn 50~70 lakhs INR / year once you complete your MS. If you manage to save good amount then you will able to repay the loan within 2~3 years.
Preparation :
GRE is easy to crack. You need to have lots of patience since you will have to mug up english words [which you never use again

] throughout your preparation. If you can devote 3-4 hours everyday & 6-7 hours in weekends, 3 months are sufficient for GRE.
Maths - Very easy ! If you are not confident, then get Nova GRE & solve maths from it.
Verbal - Barron's & Kaplan are enough. If you do 1500+ perfectly, I can assure you 310+. (Max is 340)
1500+ words - 310~315
2000+ words - 320~325
2500+ words - >330
There are 3 categories of words. Highly frequent - 100, Frequent - 300 [You must do these two type of words] & rest belong to less frequent. Google for list of words.
Concentrate more on Reading Comprehensions. They are tougher now compared to earlier.
Get this software called GRE Bible & you can easily do words.
Let me tell you something, instead of mugging words you could actually 'learn' them. But it takes lots of time. It's easy, you need to understand root words, pre/suffixes & how to apply them & derive the meaning. For example, 'tele' means distance, based on that itself you can understand words like telephone, television, telepathy etc etc. I liked this approach very much. Read this book called Word Power Made Easy.
Lastly, solve from GRE Big Book.
Other options :
If you are good in CS subjects then consider giving Subject GRE for Computer Science. This will be tougher than GATE, but if you manage to get good marks then you could easily land in top univs.
One more option in higher studies in India itself. As pointed out earlier, there are good colleges apart from IITs & IISCs, like IIITs etc. They even offer MS by Research, MTech + PhD courses etc. You get 8k/month stipend, for TA - 12k/month & for RA - 20k/month [not sure about these figures]. Even some top companies can sponsor you & they will take care of your all expenses during your education.
But...MTech in IITs is not as good as BTech.
However getting into good college is lot tougher since competition in GATE is very much, especially in CS. This year 2.5 lakh CSE students are expected to give GATE :-/ & I am also preparing for GATE 2013.
If you study for GATE seriously then it will be lot helpful for you to crack Subject GRE.
Hope you find this post useful. If I am wrong anywhere, please correct me
