Gammer

General English Course 全面的英話課程，包括聽、講、寫。可以很活也進行。例如日常生活中角色扮演來學習應用，看電影聽歌...視乎導師。
Grammar Course 只學文法。如句子構造、句式、詞類...。比較難生動地進行，可能會比較悶。
學習甚麼都該建立了興趣先，有了興趣，之後甚麼都好辦。

General English Course would likely to teach you every aspect in English, including writing, listening, reading, speaking.
As for grammar course, it would on grammar rules, such as tenses, preposition, article...
Choosing between the two, u should know what you expected to learn and your weaknesses in English.
Good luck