I didn't notice this thread until today.
So there are two main types which have their various strains, Indica and Sativa. All the marijuana that you buy will be hybrid of the two, if you are buying from a dispensary they will usually give the approximate make up (80/20, 50/50 etc).
Indica heavy strains are higher in compounds Cannabinol and Cannabidol, those are the ones that are most beneficial due to the anti-inflammatory & muscle relaxing properties. They interact with the CBD2 receptors lining the gut and provide relief. As such due to the muscle relaxing properties, indica heavy strains are the ones that cause the body buzz (couchlock) and can make you sleepy.
Sativa heavy strains will be higher THC and lower in Cannabinol & Cannabidol. These strains will have more of a cerebral high and less of a body buzz, sleep inducing effect.
The majority of the stuff that you buy from the street will be indica based due to the how the plant grows (sativa tends to be a taller plant, whereas indicas grow to be shorter and stockier, this trait makes indoor growing easier as there tends to be less vertical room).
With that being said, when I was smoking more consistently, I would smoke at night before going to bed, this allowed everything to do it's magic, the lingering effects would help the next day, I was able to sleep better and I was never a fan of being high. I found if I didn't smoke for more than 3 days I would start noticing and increase in washroom trips.
Any strain of cannabis will help, some help more than others, there is no one size fits all as people will enjoy different strains. It is best to experiment. A dispensary will most likely you buy in 1-2 gram quantities so you can mix and match to create a sampler. You may also wish to purchase different strains for use during the day and one for night.
Edible products are very beneficial as they are absorbed directly into the GI tract, if the dispensary you go to sells they they tend to be consistent in dosage, however they physical effects will last a lot longer. For me I would still be feeling a mild buzz upwards of 10-12 hours later, but yet again, everyone is different, your mileage may vary.