Your home theater audio setup will depend on the space available to you, what kind of signal your receiver can carry, and the number of speakers you have. With proper setup, it doesn't matter if you have a simple stereo audio setup or a complex multi-speaker setup.
Proper home theater audio setup will give you the most enjoyable experience.
The first step to proper home theater audio setup is if you have a tile, hardwood, or any other non-carpeted floor, to put down an area rug. Hard floors may look nice but they affect acoustics poorly.
The second step in home theater audio setup is to place your speakers. For a stereo setup, placement is simple - one on either side of the viewing area. For Dolby Digital 5.1 or Surround EX, however, you must take extra considerations into mind. Your center speaker should either be on top or below your display and facing your primary viewing position. The left and right front speakers should be on either side of the screen, preferably at ear level, at about a 45 degree angle from the center of the viewing position.
If the seating is meant for more than one person, all three of the front speakers should be placed in a straight line.
Surround speakers should be placed slightly to the rear of and alongside the seating, a few feet above
head level when sitting. If the surround speakers must be placed behind the seating, experiment with
pointing the speakers at an angle so that the sound coming from them seems to 'surround' the viewer. If
you have a subwoofer, place it wherever is most convenient, as it's placement is not critical to sound reproduction.
When you are using Dolby Digital 5.1 or Surround EX, it is necessary to continue your home theater audio setup by configuring your receiver. Unless you have tower speakers, all main speakers should be set to 'small'. Low frequency effects and bass should be set to subwoofer if you have one. DSP modes should be turned off. Read the user manual to find out how to change these settings and to double check any special requirements you receiver might have.
With proper home theater audio setup, you can have a truly enveloping aural experience.
... and don't forget to get your speaker stands!
and flat speakers too!