Q. Is someone does not understand the Hebrew or the Targum, does he comply if he listens to a tape? or even if he just reads it from the chumash, without knowing what he is saying?

A. Poskim disagree Yalkut Yosef ( 4: 285: 3) asserts that one should read both the Biblical text or the Aramaic translation even if he does not understand it. Mishna Berura (285: ) writes that there is a special quality to the targum since it was given in Sinai. (See Yehave Daas 2: 37).
However, Chukei Chaim p. 41 debates whether one complies at all when reading something one does not understand. See Likutei Amorim 5, for a similar opinion.
Teshuvos Vehanhogos (3: 98) rules that one does not understand the Hebrew or the Targum, should read them anyway, followed by a translation he does know. (See question 263 in regards to the correctness of translations).
Horav Shlomo Miller’s Shlit’a opinion is similar.

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit’a