there are peds/emergency medicine, peds/psych/chid psych, psych/child psych, and peds/IM combined residencies; there are also a few peds/genetics integrated programs (UCLA, CWRU, Mt. Sinai, CHP, UCONN, NCH).
as for subpsecialties, there are peds pulm/critical care, peds cardiology, adolescent medicine, peds GI, peds infectious disease, peds endocrinology, and others, I'm sure.
Child psych is normally a fellowship after psych residency except for the combined programs listed above. it depends if you want to practice peds in addition to child psych.
Peds surgery is a subspecialty of surgery.
I think there's also peds pathology and i've yet to see a pediatric pathologist.
As for lifestyle/income, peds, on average, make less money than any other field (avg. is usually $110,000, i think), not including those who specialize. it depends what setting you want: private practice, regional hospital, university. what i saw in suburban practice and what i saw at the university clinics are two different things.
also, if you want to go into peds, you must understand that a good chunk of your time will be doing "well child" visits at certain milestone ages, especially in private offices and suburban clinics.
in the suburbs, you see mostly strep throat, OM, URI, asthma, ADHD checks, etc. once in a while you'll see hernias, heart defects, STD's, and other infections like pinworm or intertrigo. at the university, you'll also see rheumatic fever, HIV, cystic fibrosis, PKU, etc.
-s.