Design Question For Survey/questionnaire Type Application

I am a developer and I have a problem trying to design a system to
manage data coming from web surveys. On average each subject will take
part in more than one survey and each survey may potentially have 100+
questions.

I am focusing here only on the table(s) that will hold the survey
data.

I'm thinking about having a wide table storing each question in the
survey(s) as a column against the subjects. My main concerns with this
approach:

- the "yuckiness" and potentially other performance issues(?)
associated with a table with 100s of columns
- the 8kb size limit per row (unlikely to touch it, but possible)
- 1024 column limit (unlikely to touch it, but possible)

Another approach obviously is to have a single table where we have, in
a simplified version, 3 columns: person_id, question_id and data/
answer. The problem with this is that the "data" column will have to
accommodate
all types of data, from bits to varchars, and that field validation
seems now impossible jeopardizing data integrity, and most
importantly, you can't easily work with the data in filtering/
reporting etc.

What do knowledgeable designers come up with in this case? Can someone
point me in the right direction?