I have heard a lot of positives about Rosetta Stone. Even before they started advertising on television. I believe they have demos on their website that you can check out.
As far as Spanish goes, whichever software you decide to use, find a copy of "501 Spanish Verbs" by Christopher Kendris. It helps immensely with conjugation. Since we don't conjugate similiarly, it helps in learning the patterns. Once you learn Spanish, then Italian will be a breeze (both latin based). Japanese is a whole 'nother enchilada. Good luck.