Releasing one version of a Scientific Paper under an Open License I am going to release a Technical Report that will be archived and made available online by the university's library. An abridged version of the work was accepted by a peer-reviewed conference and will be published in the proceedings. For this to happen, I have to sign a copyright form, assigning to the publishing institution all rights under copyright.

My questions:

a) What is the best way to grant readers of the Technical Report the freedom to quote (unlimited length), distribute, and build upon the work? And point out that they have this freedom without asking for my permission?  

b) Is a Creative-Commons License the way to go? If yes, in what form should include the lincense in the work?

c) Is there any conflict between the copyright form for the conference paper and releasing the Technical Report under an open license?
A Creative Commons License is a good way to achieve this.  It doesn't really matter how you convey this information, as long as it's clear.  (A footnote on the first page is fine, for example.  Whatever you prefer.)  The attribution license (CC BY) sounds like a good choice for what you're looking for.

However, this definitely conflicts with the copyright form.  You can try asking the IEEE for permission, and there's some chance they will agree, but they tend to be picky about copyright.  If you can't come to an agreement with them, then you will have to decide whether publishing in this conference is worth giving up copyright, and they will have to decide whether it is worth losing your paper over this issue.  (If you have already signed the form, then there's nothing you can do except ask them.)