re: binary 65

It's not so difficult. In the case where the data are intended to be read many (hundreds of) years down the road, say to be deposited in a time capsule, then people can design the encoding to be as readable as possible. There are some standard tricks that can be borrowed from basic data transmission protocols: stop bits frame bytes (letters) and perhaps rudimentary blocks with checksumming. A document designed for long-term storage would also have some preamble material which can be used as a guide for understanding the rest of the document. Since you mention ASCII, we could include pictorial representations of the letters alongside the binary-encoded forms, for example. Similarly, a rudimentary vocabulary might also be included, perhaps also augmented with pictorial forms. Or perhaps the document would eschew English entirely and use a set of hieroglyphics (encoded in binary from the included pictorial dictionary). One fascinating possibility, I think, would be to encode information at different scales. At the highest level, a pictorial representation of a lens could direct the savvy reader on how to construct a tool for reading the rest of the text, for example.

Even if the document wasn't created with the intention for it being read many years hence, if it encodes language strings (rather than just program data, say), then there are standard analytical techniques that can be brought to bear. Provided the future reader has a modicum of mathematical ability and (presumably) the ability to transcribe data off the glass, given enough text it should be possible to discern lexical features (basically letters and words), syntactic elements (distinguish verbs, nouns, tenses, pronouns, etc.) and from there start working on the semantics of the message. I think that the task of finding a message that's worth reading would likely be much more difficult than the task of decoding a useful message, should it be found.

Overall, I wouldn't worry about ASCII (or EBCDIC or whatever) being a barrier to future understanding. There are two much bigger problems: how to ensure that we have a worthwhile message to transmit (and that it can be found) and that there will actually be anyone around to read it. On that scale, worrying about ASCII is pointless.

Bonus link: http://en.wikipedia.org/wiki/Into_Eternity_(film)