The purpose of this research study is to find out if treatment with rituximab in combination with aldesleukin (compared to rituximab alone) decreases the risk of cancer returning, as well as determining what other effects (good and bad) this drug combination has on NHL. Rituximab and aldesleukin are not approved in combination by the Food and Drug Administration (FDA) for the treatment of non-Hodgkins lymphoma; however, Rituximab is approved for use by itself to treat NHL.