The FSI[1] has ranked languages according to how easy it is for English speakers to learn. There are 10 languages in Category I (the easiest to learn)[2]:

Afrikaans, Danish, Dutch, French, Italian, Norwegian, Portuguese, Romanian, Spanish, Swedish

[1] http://www.state.gov/m/fsi/

[2] http://web.archive.org/web/20071014005901/http://www.nvtc.go...