Most images look better with pronounced color. Some shots can be made to look better, with black and white, given a few conditions:
1. High Contrast. With many tones between white and black, an image will truly shine when made
black and white. The closer your images are to a unanimous color, the worse they will look in black and white.
2. Monotone Color. Sometimes you can't help the colors you are given. Shooting a forest is going to give you a lot of green, shooting in winter will give you a lot of browns. If your scene has a lot of the same color, switching to black and white may give your image a little pop, allowing you to focus on the contrast and not the monotone colors.
3. Artistic Vision. Don't just apply a black and white filter on all of your images. If you feel that a vignette (darkening of the corners and edges) and black and white will add an artistic flavor to your images, go for it.
Remember that the best camera is the one that's in your hand. Keep shooting, and take care.