In answer to your questions:
1) If someone registers as a job seeker, they can complete the resume form which includes the information you describe, as per the
example on the JobRoller demo. Outside of this though, it would require customization on your part if you were looking to add this as part of the actual registration process.
2) If posted as a resume, yes you can allow employers to search through these.
3) Yes, JobRoller has an option which will allow you to charge employers to view the resume pages.
4) Resumes can be searched by keywords or location as shown on the
demo.
5) As mentioned above, yes.
6) By default, these are separate charges.
7) Yes definitely, JobRoller is not encrypted, so you are free to make modifications as you wish.
8) By default, users do not have to be registered to actually apply for jobs.
9) There is a basic profile like this already available if you select the job posters name link e.g.
here.
Thanks.