@Matrix
Brush vs brushless: Brushed are typically cheaper (and can use cheaper speed controllers), while brushless are lower maintenance and slightly better efficiency.
As for batteries, all the voltages you have listed relate to LiPo (Lithium Polymer) batteries, which require a better charger than NiMH (Nickel Metal Hydride), which are typically 7.2 or 8.4v
For LiPo each cell has a nominal output of 3.7v and are connected in series, so 2S=7.4v, 3S= 11.1V, 4S=14.8v etc. (you will need to make sure the speed controller etc are rated for the voltage of the battery 2S is the norm and most will handle 3S without too much issue)
The higher the voltage, the more power the motor will output (roughly speaking, there are other factors that effect this, such as the number of winds for brushed motors, lower = more power.......for Brushless higher KV = more power I think...I'm a bit rusty on the details!)
The value that will have most impact on how long the battery lasts is the capacity (mAh, so for both the batteries you've described this is 5300). Btw, the 40C rating is the highest rate of discharge the battery is rated for, meaning more power but can run out quicker....40C is mid range-ish!
I have a Maverick Strada Drift/Road car myself and they are a decent introductory kit for a beginner (although I changed the motor in mine for something a bit pokier!), they come fully assembled and with everything you need (apart from maybe some AA batteries for the controller), I'm not sure if the Abisma kits require any assembly and definitely require a bettery + charger to be bought separately.
Regarding batteries, I'd probably recommend getting a half decent fast charger (start around £40) and 2-3 small to mid size batteries, as they won't last too long either way, but you can charge another and swap them with relatively little downtime.
If there is an RC hobby club in your area they'll probably be able to give you better advice than I can, or call the shops, they're usually staffed by people with a lot of knowledge on the hobby!