If you look on the italki list, you'll see that it is French, then Spanish. No language is easy to learn.

Well, you have an idea of what languages are most spoken, as for what languages are easier to be learnt, that will dependend on your current knowledge. You already speak Chinese and English, if you want to be safe, choose a language that relates in one way or another to the knowledge you already have. You may go for Japanese since you already know most of the symbols (with little differences maybe) that you will have to learn. Japanese is very poor in phonetics so, you should have no problem with that, though Japanese grammar is a lot more complex than Chinese. You may also decide to go for a germanic language given your knowledge of English and the fact that most of them have very little or easy to predict changes in declentions. Grammar tends to be very easy also. Some sounds may be difficult though, specially in nordic languages. Roman languages are easy to pronounce (maybe French has more complex sounds) but they have a very different grammar from what you have seen and decrentions are very intrincate sometimes.

Spanishh lool In USA its the second language english obviouslyy is first. Like even in Canada in the product labels they're starting to add spanish so now in some products you'll see english, french, then Spanish.

The most popular languages, in order are: 1. Mandarin - 1051 million - China, Malaysia and Taiwan. 2. Hindi - 565 million - India, northern and central regions. 3. English - 545 million - U.S., UK, parts of Oceania. 4. Spanish - 450 million - Spain and the Americas. 5. Arabic - 246 million - the Middle East, Arabia, North Africa. 6. Portuguese - 218 million - Brazil, Portugal, Angola. 7. Bengali - 171 million - Bangladesh, northeast India. 8. Russian - 145 million - Russia and Central Asia. 9. French - 130 million - France, Canada, West and Central Africa. 10. Japanese - 127 million - Japan