Yes, you will be able to limit the file types for a file field. You can apply a validation on the field to check for the extension you want.
You will not be able to validate for the size of the file using the product.
You can set the file upload field as an attachment to an email, but that is not part of the functionality of the product. The product basically builds forms for you and allows for you to validate these forms. To accomplish this you can use the Digital File Professional and Universal Email products that we provide. There is a tutorial (under How To's) on how this can be done with those two products on this page: