Computers & IT (Non-Engg)

If you want to join a IT company or IT-Infrastructure wing of any MNC than MCA is best option. If you want to go in teaching/research field than M.Sc is better option.

You can get a job with a degree in B.Sc CS. It's one of the best courses to get a Good job in private sector. But if you want, you should do M.Sc to get a highest paid job. Even I'm a B.Sc CS and currently working as a IT Analyst with TCS :)

Yes, its really a good option, placement is also very decent.

Yes, absolutely, you can take admission in B.Sc in 2017 provide you clear their eligibility criteria and age limits (is any). None college can deny your admission! but college might ask the affidavits for this 2 year of gap!

Ethical hacking is a broad field in itself and deal with many kinds of attacks, and some sophisticated too.
Every IT organisation which is dealig with USERS and their data with privacy contents needs an ethical hacker to secure their domain.
If we talk about SCOPE.
Yes there are loads of STARTUPS , aka

B.E. is better option, engineering graduates in computer are still in great demand. Many IT companies and non-it companies with there IT infrastructure do need Computer Engineers. B.E. is Better option.

It seems you are not putting an effort in theory papers. Any recruiter looks at the overall performance of students. Therefore, you are advised to put the effort in all papers equally to score well.