pc fan and power supply questions

ive got everything else down, but im still a little confused on what power supply to use.
i have read i can use phone chargers, i want to be reading the output volts right? i have 3 spare ones i found layin around, one 12v, one that says +5v (does that mean i can use it on higher voltage things?), and one 4v. i would only use the 12v right? the others would be too slow.

what else can i use to power them? i found these, http://www.newegg.com/Product/Product.aspx?Item=N82E16812706011&cm_re=12v_ac_adapter-_-12-706-011-_-Product

would this work?

im also pretty sure ive got the concept of splicing wires. connect black to black and white to white and tape em up.
i appreciate the help, sorry if its confusing.

oh ya and i am going to be using these fans http://www.newegg.com/Product/Product.aspx?Item=N82E16811998127&cm_re=120mm_fans-_-11-998-127-_-Product
3-4 of them
ill buy them unless anyone recommends ones with better CFM for the decible level and for the price. i just found them in a couple minutes didnt look at all of them, they seem alright

if its any help, i attached a multi adaptor, which has a switch that goes from 5v up to 12v. (from what i can recall, cud be wrong with the figures though)

this allows you to control the speed of the fan, but im not sure if its safe running at lower voltages.