Snap Track is a brand of sectional track that is aimed at beginners. The snap track switch is a regular curved section in one direction and a regular straight section in the other direction. It preserves the geometry of a simple layout so that you will have no cutting and fitting.
Sectional Track generally offers a variety of curves, turnouts and crossings, but not straight tracks. That is you would use three foot lengths of "flex-track" as your straight pieces. There will be cutting and fitting, but the geometry will look more realistic.
Flex track allows the use of flex tracks for all tracks and curves but anticipates the use of sectional turnouts and other "special work".
Hand laid track is something else all together. You buy a bag of wooden ties, and lengths of loose rail, and you build everything yourself. Some people who use hand laid rail will nonetheless use pre-built (sectional) switches, others will build their switches and other special work from scratch. Those who as build their own switches tell us that it is easy, but I have never even thought of attempting this.
Bottom line, you probably want to use sectional track of some sort, especially if you will be building a long thin layout without any loops. The LION thinks this is what you should do, and you should become used to cutting and fitting tracks together. LION will not build switches, but him has no problem cutting them up and fitting them to his layout.
Here is some of my track work. It is not world calss, and many adjustments have been made since this photo was taken. The rear four switches are "Snap Switches" as described above, the switches in the foreground are No. 4 "Custom Line" switches.
