I tried Busuu & BBC and found them both quite good especially bearing in mind that they are free to use.
The BBC has interactive courses, video courses vocabulary lists etc.
They also have TV shows for some of the languages that you can use with their on line material. I am not sure though If they still broadcast these shows.
They have quite a few languages available but I noticed that many of their language pages haven't been updated in years.
The page is certainly good to get the basics when learning a new language. Not sure it is suitable for advanced learners ( I never made it that far
)
Busuu has well structured courses with varying topics. Busuu also has quite an active community.
You can get your posts or voice recordings corrected by a native speaker. There is also an integrated messenger so you can chat in real time with people from all over the world.
The only downside is that so far they just have a small selection of languages available.
As of yet they do not offer the language I would like to learn. So for now I just log in every now and then and correct other people's postings.
None of the two sites are suited for small children though.
Hope that helps....