Javascript for the front end, but you'll need a php/perl/.net/whatever backend to email the data to yourself or store it on the server.
Sorry, don't think Excel is quite that robust
<--- Software, apps and programming might get you less yelled at.
Edit: Re-reading the OP, sound like you don't want the information, but just want to display a certain product for them at the end based on their answers? If that's the case, it's a Javascript-only job.