Yes, you can have an input into the choosing of your examining team (in discussions with your supervisors). However, the 'people' who ultimately select the examiners are the University's research degrees comittee. They will look at the CV, list of publications, status, examining experience etc. of the proposed team and will either approve or reject. Usually, there is at least one external examiner (i.e. from another Uni) and one internal examiner (i.e. same uni as you but must not have had any input into your supervision).