The old CD probably won't get you far, mainly because it likely only supports Windows/Mac from the early 2000s, and on top of that, the methodology just isn't current anymore. Rosetta Stone was the thing back then, but nowadays there are better alternatives. The principle of "learning only with the target language, no grammar explanations" can work, but it just needs more context than a rigid CD program offers.
Duolingo and similar apps haven't replaced everything - it really depends on how you want to learn. If you like an app that's short and game-like, where you can just do something quick in between, then yeah, try Duolingo or Babbel. But if you want to get into it more intensively, YouTube channels, interactive websites like Busuu, or even good old textbooks (available digitally too) might work better. I wouldn't recommend dusting off that CD - the effort to get it running and then actually work with it isn't worth it when there are free or cheap alternatives that are more modern and will be more fun for you.