What contact form plugin do you recommend?

Greetings:

We just need an easy-to-setup contact form that allows uploads of text files that are sent to the webmaster / super-admin where the attachment is not embedded (it is an attachment).

What plugin do you recommend and why?

We are currently using “Fast Secure Contact Form” but text file attachments are embedded into the body of the email, and that kills the formatting.

Thank you.