Which track is better depends on what your long term iinterests are. For setting up and taking down, using on the dining room table, or similar non-permanent situations the Bachman EZ track is probably better. The Bachman EZ track, LifeLikePowerLoc, and the Kato track with the built-in roadbed are all incompatible with each other and any other make of track, which restricts you to only sizes and pieces they make.
For a permanent layout, the Atlas track offers more flexibility in track configuration. In addition to their published layout plans, Atlas offers free track planning software called RTS. Another advantage is that all the non-roadbed track makes are pretty much compatible with each other. But the non-roadbed tracks will not hold up as well to being repeatedly set up and taken down. The Atlas Code 80 N track is recommended for beginners. The Code 55, although looking more realistic, will not handle all N trains right off the bat.
As far as wiring goes - yes you need a separate controller called a "power pack" for each train that will be run at the same time. It's highly unlikely on a 3x5 layout that you will be running more than 2 trains at the same time. You may have more locomotives on the layout, but getting more than 2 people around the layout to run their trains will be difficult even if you had the track to support it. So a relatively simple "cab control" wiring system was developed - for which Atlas sells components - that allows 2 power packs to stay connected to the train they are operating, no matter where they go on the layout. The track is divided into electrically separate "blocks", each roughly a train length or longer long. A slide switch on the Atlas Selector is wired to each block. The switch is moved to connect the block to Power Pack A or B or turned off (slide switch in center position). The blocks in use by train A are connected to Power Pack A and so on. Blocks where an engine is sitting but not being used are turned off.
On an oval of track, you generally want at least 4 blocks for good operation. Sidings that could hold a train or might be used to store locomotives should also be separate blocks.
Hope this helps.