But i think there is a deduction of 2.5% i do not do this i.e. if i include physical education.plz tell.....

When you apply to DU, and you’re applying for basic courses like Phys, Chem, Math hons or even courses like History, Eco or Psy. for that matter, your B.O.F WILL ONLY include the 3 main subjects (P,C,M) + English (and a 2% deduction because of stream change).English is ALWAYS counted in your B.O.F.The only way you can calculate your Best of four with physical education is if you want to go for a Phys Ed course.

Can i exclude physics and include physical education in place of it ????????

No you cannot.
You only add phy ed when you go for physical education course.