Welcome to the forum!
If you want a small size factor a lot of poeple on this forum found the Volt to be a satisfying first kit experience. You might also consider an Ego-C kit from Joyetech ( lots of vendors have it) . It is a tank system, so you won't get the best flavor nor the highest throat hit but it is very easy to use, easy to try different juice flavours and the batteries are compatible with a lot of different types of cartomizers, clearomizers etc.
A genuine joyetech ego-c should cost around 80 USD, it comes with 2 batteries, 2 atomizer cones and 5 spare atomizer heads. You can either have the 650 mah batteries witch are smaller or the 1000 mah batteries. Two 1000 mah batteries will provide power for an entire day even for a very heavy smoker.
I wish you all the best for your journey into vaping and i congratulate you for trying to get off analogs. You will see some major benefits in a couple of months after quiting the darn analogs( i smoked one pack a day of analogs for 11 years)