Accounting & Commerce

If MA eco is your goal don't go for B.com(H).
Entrance exams of various universities foe MA.ECO have a lot of math,econometrics,introductory micro and macro economics as well as welfare economics,etc. which are not taught in B.com(H) and B.com programme.
B.com(H) and B.Com programme are accountancy based course with some subjects related to business management or Business studies in layman language.
Hence,If you wanna go for CA/CS/ICWA/MBA/M.COM than B.COM(H) or B.com programme is best.And if you wanna go for MA eco than BA eco hons is better.

Yes math is compulsory in DU for B.com(H) and B.A.Eco(H).But you can go for B.com programme if you don't have math as an elective subject in class11 and 12.

Yes you can. Start visiting the https://Shiksha.com website panel and talk to admission executive. He will guide you in right way. Also start searching for colleges which has acceptance of 44% B.Com in their college.

According to me, BCA would be better. It depends on your choice of interest.

You can not do two degree simultaneously in majority of universities unless there is a provision of dual degree in university. Mumbai university does not allow M.Com & MBA simultaneously.

North campus is impossible to be honest.
You can get colleges like Motilal Nehru College,Deshbandhu college,Shaheed Bhagat Singh Evening,PGDAV,etc
For more information check 2015's cutoff list.
Add 0.25 to 0.75 to find out the anticipated cutoff for 2016.Though results will not be accurate but they will atleast give you an idea. All the best mate!!!

You have bright chances to get admission.