for better find you have 2 way more :

1 - you can also see the list of all games you have take screenshot under steam=userdata=(bignumber)=760=remote =... (exempl : 222880= insurgency , 72850= skyrim , 231430= company of heroes 2 ,etc...) have an screen make more easy to see wich game is what

2 - you can simply make an right clic on your desktop icons of steam games and select "property" , it will show you the game path (exempl : steam://rungameid/314830)

none.

all the F2P games work exactly same. you need to buy 9$ of ingame stuff for get 1 card from them. its same politic for all the F2P game ,DOTA,TF2,etc..

for the best, its up to you . if you prefer war style TF2, or strategy style Dota, ,etc..