When writing Sec+ or S+ we mean Security+ by CompTIA, yes.

I would recommend to go the other way round, first Security+ and then CEH.

Well, Security+ is a cert which covers mostly basics. Although CEH is said to be an entry cert as well, I would say it is more advanced than S+ and therefore I would recommend first S+ and thenafter CEH.

Which topics on each cert will be covered can be read on their websites. Shortly said, S+ covers many fundamentals and concepts and CEH is very tool-based.

Sec+ and CEH cover slightly different concepts.  Both of these certs are fairly respected by employers, though I doubt they will be enough to land you a job.  I would concentrate on picking up knowledge and experience and then go for certifications.   

Kind of on the same note as ketchup... Don't focus on the cert itself, focus on learning.  The cert is just a slight bonus.  If you don't have any work experience in the field, it doesn't matter what certs you have, they're still gonna stick you in an entry level position (or close to it).  So instead of getting extra paper, get the knowledge to prove yourself once you get that position.

I'm not saying don't get any certs, cause they can help you get through the door.  But make absolutely sure you know what to do when you get there.  If you search around the forums, there are plenty of stories about "paper tigers".  People who have a ton of certs, yet still don't know what they're doing.  Nobody wants to be on of those guys.

All in all, study for the cert that you will learn most from.  Since you're still in school, I would look to take advantage of an internship.  It's a great way to get work experience.  On top of that, there's always a decent chance to get hired at the end of the internship.

I would say that Sec+ is a perfect candidate for self-study.   I would also say that it's a closer stepping stone to CISSP and not CEH.   If you have time, pick up a few books and go for it.   It covers a fairly broad range of concepts that will help you down the road.

Sorry, I meant in terms of what the covered concepts and not degree of difficulty (which is relative).  CISSP covers a wide area of conceptual knowledge and requires quite a bit of experience.  CEH deals primarily with ethical hacking, pen testing, and vulnerability assessment concepts.   Security+ also covers a fairly wide range of conceptual topics, although not as wide as CISSP.   

I wouldn't worry about degree of difficulty so much.  It's all relative and you have to start somewhere. 

Job314,
I didn't mean something bad with entry level certs or wanted to lower their value - I will start soon myself with CEH as I think it is worth the efforts.

As already stated, CEH and S+ cover some different areas, so I don't think that a CEH course would teach you enough to pass both exams without extra study materials. Especially for S+ you should be able to find some books and online resources, which should help with self-studying and actually getting the S+ cert.