Hmm. I would question (heh) making the Questions a single field. After all, if a question gets changed, old answers are no longer valid.
I would personally make each question a seperate field, and each record is one person's responses to each of the questions. So, you would have:
Question 1: {Answer}
Question 2: {Answer}
etc.
If you needed to run a different questionaire later, leave the old fields intact, but simply create a new layout with new Question fields, or duplicate the old database, delete all the records and change the questions. The former lets you keep all the responses to all the questionaires together (while hiding old ones from the users), while the latter lets you organize each questionaire into seperate, smaller databases.