Should I apply I-130 form for brother with physical disability?

The question at the end of the process is whether your brother will be able to be supported financially in this country taking into account his medical condition. If you are well-to-do or have such a financial co-sponsor, your brother may still be able to immigrate despite his physical disability. I suggest that you put in the I-130 petition at this time and see where you are when his priority date is close to becoming current. Due to the limitations of the Lawyers.com Forums, Alan Lee, Esq.'s (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.

Our immigration policy does not discrimnate against the disabled.  We perform medical exams on immigrants to ensure they don't have a communicable disease.  You should file for your brother.  You will have to file an affidavit of support for your brother which will effectively make you responsible for any public charges incurred by him after he arrives in the US, not the taxpayer.