A lot depends on how you plan to use them.
First about the beam angle. A small beam angle is less distance sensitive. This means you can detect things at further distances. If you were doing line following, this means changing the height of the sensor to the ground has less effect to the line detection ability. A wide angle beam is more likely to see thin objects, such as chair legs. Also dont forget intensity of light. More candela is better.
Also, you do not specifically need to use infrared. Any wave length will work. You can easily use a pretty bright green LED and a simple photoresistor. I have a robot that glows a bright neon green because of this. Works well AND looks cool.
The advantage to infrared is that the human eye cant see it, and that infrared generally has a higher response speed. Just make sure your emitter and detector both operate on the same wavelength (should be specified in the datasheet). Also recommended not to use a wavelength of light found in the environment your robot will operate in.
Side note, you do not need an equal number of emitters to detectors. One emitter and 10 detectors will also work . . . just depends on what you are doing.
Those parts you list look right. I didnt check the wavelength though. They also sell some that have the emitter and detector built in to the same package. There is a huge variety out there, I recommend looking around.
