The day I went to my alma mater, BIT Mesra I was asked alot of questions on whether to take Science/Engineering optionals , and about other Humanities optionals...in my humble opinion no one person can guide you with regard to all the optionals and since my batchmates have put in an effort to explain their strategy via blogging...I would ask you to also refer to their blogs :
For Science/ Engineering optionals please refer to:
He is Rank 2 , a true techie, aimed for a 100% in his optionals MATHEMATICS and ELECTRICAL ENGINEERING and got it too :)
He is rank 24 and has given a comprehensive listing of books that he referred to in PHYSICS and CHEMISTRY
A question was asked by a BITian that, the common perception is once you take up science/engg optionals you face competition from IITians...my answer would be- So what??
The point here is whether you are comfortable and super confident with your optionals,your concepts are clear,and are willing to work very very hard...
A non IITian who topped the CSE is a good example to draw from:
Muthyala Raju Revu(AIR 1, CSE 2007)
Thanks to Anay (rank 5) I got to know that Maitrey Kulkarni(rank 103) from our batch has MECHANICAL ENGINEERING though I have no blog details...maybe he could be contacted through the social networking sites facebook and orkut.
Some Engineers who took up humanities optionals:
AIR 5, He has exceptional marks in PUBLIC ADMINISTRATION and has discussed on his very well organised blog not only strategy for pub adm and PSYCHOLOGY but also sample notes,his mock test answer papers and inter alia the manner in which a newspaper reading should be done ....very detailed ....he has saved all of us alot of effort !! :D
AIR 13, She scored extremely well in HISTORY and PUBLIC ADMINISTRATION and has discussed respective booklists in her blog.
3.Tanvi Sundriyal...I have decent marks in Sociology (esp paper one,trying very hard to be modest here :D) so you can refer to the booklist and strategy I followed in this very blog.
Though for Paper II I would recommend another Engineer's blog
Rajiv Ranjan Singh(AIR 191) chose SOCIOLOGY and PUBLIC ADMINISTRATION and has given a detailed write up on the notes and books that he referred to in Paper II- Sociology
Also he is the only person that I know of who prepared and got through alongwith a job (in TATA STEEL) so he would be the best person to tell you how to prepare alongwith a job.
AIR 1 in CSE 2008 ,her blog was referred to by some of my friends esp for PUBLIC ADMINISTRATION...though now she doesnt write on CSE prep , older posts on her blog might be helpful.
A doctor (AIR 8)who took up SOCIOLOGY and PSYCHOLOGY has shared her personal experience,strategy,booklist , and stuff on answer writing and time management on
http://www.garima-mittal-ias.webs.com/A MBA (rank 25) has shared notes and tips on Zoology(by a friend),Geography, Essay etc
Law graduates from NLS Bangalore Ashutosh Salil and Cyril have discussed LAW preparation on this very blog...
Hopefully my strategy of " Passing on the buck" has worked well for all of us!!! :)