Hello Safwan,
There is nothing like a better course. We should know the basic difference between these two courses.

B.com is the Bachelors in commerce and subjects included in this are : corporate accounting, finanace law, micro & macro economics, company law etc..,
BCA is the Bachelors in Computer Application and subjects included in this are: database, networking, data structure, core programming languages like 'C' and 'JAVA' etc..,

As you have interest in computer science so you can choose BCA or B.tech in computer engineering but keep B.com also in your choice for MBA as it has several subjects that are from commerce which creates a base for doing MBA in future.

Hello,

Both the courses have different scope in terms of job prospects.

Doing BCA from good college will give you jobs in computer system and programming.

While B.COM+ MBA will give you great opportunity as you will have post graduation degree. You can do your MBA in marketing, finance ,Internation Business, Decision science, Supply Chain management, whichever field suits you.

MBA will definitely give you an additional advantage over just doing BCA. You can persue MBA even after completing your BCA. But whichever course you select, do it from a very good college. 

Hope you got your answer. I wish you all the best.