Before you can pick a good mutual fund, you have to know what they are.
Mutual funds are basically a pool of money that many investors put together.
When you invest in a mutual fund, you end up owning a tiny portion of each share of stock or whatever you've purchased. Each mutual fund invests in different things, and each fund has different goals. Income funds also invest in bonds and have lower chances than a growth fund of making a lot of money - but they generate present day income. Mutual fund companies have various fees and commissions that they charge in exchange for their services. All funds though charge management fees and some charge marketing fees as well.