Google forms are probably the simplest data collection tool that you could use, with the added benefit that data is neatly collected into a spreadsheet, ready for analysis. You will need a Google account to create forms, but no account is needed to use one.
Although not very sophisticated in that conditional branching isn’t supported beyond changing sections based on a single selection, the style of ‘new’ Forms has been greatly improved and forms can be embedded in NILE content items. Quick charts can be generated directly from the form or associated spreadsheet. It is possible to use the content of a Google Spreadsheet (using Google Apps Script) to generate an HTML page or data feed, so you can publish updates to a web site directly (and almost in real time) from a Form.
However, Forms should never record personal information (such as names and emails together) due to issues with Data Protection. This could cause a problem if your survey recipient wishes to withdraw a response, so make sure you make it clear to respondents that they will need to supply you with the date and time of their submission to your form … or ask them to submit under a nickname only they can identify.
This very helpful guide – written from a teacher’s point of view – will get you up and running quickly: