what do you think of Icelandic?
Icelandic is a highly conservative language, i.e. it has changed very little over the centuries. This means that it is practically the same language as Old Norse, the language of the Vikings. Icelanders today can read the old sagas with zero training.
Icelandic has kept case endings and the three genders (masculine, feminine and neuter).
The closest living language to Icelandic is Faeroese.
Icelandic, Faeroese and Nynorsk are grouped together as Western North Germanic. Sometimes just Icelandic and Faeroese are considered insular Scandinavian. The two Norwegian standards (Bokmaal and Nynorsk), Danish and Swedish are sometimes considered continental Scandinavian.