I use Capture One for Raw Conversions. there is also a raw converter that comes with the software bundle of the rebel, as well as a built in raw converter if you are running photoshop CS2. I prefer c1, i like the interface better than photoshop and i seem to get better results (but that could be because i have gotten used to its controls as i have been uisng it for a couple of years). the one advantage of the raw converter bundled with the canon is that canon does not release camera profiles so the companies that put out 3rd party raw converters have to reverse engineer camera profiles for them.
you can also use google's picassa for basic file management (it can view the Raw files which actually surprised me). my fundamental problem with picassa is that the folder view does not appear to support a directory tree view feature which i find frustrating because of the way i create directories. i create a directory for each round of RAW files i pull off my camera, then create a sub-directory called "developed tifs" for each one to place the raw files processed into tif files, then another sub for "edited tifs", then "resized tifs",then "jpgs for printing.". because picassa simply lists the directories either in order of date of creation or date of last modification, i often see like 5 or 6 directories of the same name in the directory view in picassa.
as an fyi, RAW files take up a ton of space, be organized from the outset in how you deal with and manage them, burn them off to archive discs from time to time and keep your disc defragmented. it's another step in the editing process, but believe me, it's easily the most important step in getting much much more out of your images. you can incredible flexibility in shooting images. it's the first step toward learning really advanced processing techniques. good luck and feel free to ask any other questions you have, here or by PM.