is it wise to have both ffdshow & AC3Filter install to our pc

[demetrish3]

hi,
question n.1: this is a question, because i was reading something in the forum in older threads, about having either ffdshow or AC3filter. is it a problem to have them both install?
if yes which one is better.
i read something about not recognising the language and showing hebrew. i'm having this problem in the subtitles sometimes, especially when i'm trying to put greek subtitles.
question n.2 :Also that reminds me, when i tried to install the bs.player in greek language(i think it was version 2.56), all the latter and grammar was like this: |||||| ||||||. yes! just lines.
by the way i'm using windows7 proffessional, and i think this problem is something with language in my windows.