Personally, I think you should try a certified trainer for a few sessions. A REAL trainer will look at you ...your strengths and weaknesses and any physical limitations and help you better toward your goal. It's easy to give advice online but one has to take in account the real life situation of the person they are talking too. You need someone to be there to make sure you're doing the exercises with the right form as well so you do not hurt yourself and get a more beneficial workout. Also, when you think about how much it costs to go to a dr or chiropractor after you get hurt...a three session pkg with a certified trainer will be well worth the money. The fact you said you were out of commission due to surgeries and such... not one person asked what that was for or if you're sure you are ready to get back to normal working out. Also, did you Doctor say you could? With some surgeries, you are not allowed to work out at all or have limited things you can do for MONTHS.
that's a fairly good point, I can tell you Squats are great but if your Squat form sucks and you have no one to correct it, directing you to Squats in THAT case is a horrid mistake
on the other hand you can litterally get a training certificate via the mail so try to make sure you can trust the person, ideally by knowing someone who they have gotten real results for