Pick your favorite brand and be sure to mix a 50/50 solution with distilled water, no tap water in your cooling system. If will create deposits in the system. As a matter of fact all the major brands sell a pre-mixed formula. That's what I use....it's easier since I'm too lazy to mix my own.
Don't use the long life antifreeze unless you completely flush the 'green' stuff out of your system.
The only time I would use a cleaner/flush is when there has been a lot of rust or deposits in the system...otherwise I don't think it necessary.
To truly get all the old coolant out of the system, take out the engine block drains as well...they are two small hex or square headed plugs on either side of the block below the heads. While your at it, go ahead and replace the thermostat and any hoses that look questionable.
DO NOT USE a 50/50 mix if u r going to do a flush remember the engine block is still half full of water and when winter comes u will be buying an new engine, this is not good at all use straigt AF unless u r going to pull the two plugs on the side of the block!!!!!! sorry but hope this helps did 2 engines this year because someone thought they could use 50 50 with a flush WRONG!!!! make sure u check it to make sure it is good to temp!!!