Disable the upload button

I want to do the following:
a)Change the default tagline “Submit a media file” to “Add new post”
b)Change the default upload button from “Your Photo” to “Attachments”
c)Make the upload button optional, i.e. an user may prefer not to upload anything.
d)Enable the categories section in the form.

In short I want to use it as a default front end posting form as none of the other frontend posting plugins have worked without interfering with my code.

http://wordpress.org/extend/plugins/frontend-uploader/