Cluintear, deantear, etc are the briathar saor - usually translated into English as "they hear" or "it is heard" - the briathar saor, a verb which doesn't have a person doing it but a general doing of the action, is active, though, not passive. Cluintear comes from "to hear", déintear (properly déantar?) from "to do" or "to make" (same thing in Irish, as in many European languages. thimcheall is an old spelling of tímpeall or "around". bhré (bré) is probably brí as in "cad is brí le" or "what is the meaning of", I'd imagine. Spellings have been standardised over the years. I wonder if dheall is dea-, meaning good- or well-, so deallrughadh would be well-born?

Hide means nothing to no one in Irish, but de h-Íde or de h-Ide is the correct spelling (even without the fada, which wasn't used on capitals until recently, due to printing conventions). The h- is used in Irish to make a vocal bridge between "na" and a vowel or "de" and a vowel, which are hard to say without it, so you have "de h-Íde" and "na h-Éireann".