I would say that Lightroom and Aperture are workflow solutions. They make life easy.
Iridient RAW developer gives very good results. Capture One and DxO is certainly worth a look. RawTherapee and Raw Photo Processor have also some benefits.
Zoombrowser is a petty basic image viewer/raw converter. You should definitely try other options. DPP is one of them (if you are on a Canon camera). Others include Adobe Camera Raw (if you have Photoshop), Capture One and Adobe Lightroom. If you are on a Mac you should also try Apple's Aperture and (my favorite) Raw Developer from iridient digital.