Question about writing songs for Baritone singing range

[musicfan97]

Hi,

If my singing range is Baritone and I'm trying to write songs on guitar, which keys should closest to my home (VS Away) singing area?

Am I limited to singing within particular keys (E.g C Major, D Major, E Major), or can I realistically pick between any of they keys, without any real cons to deal with?

I ask this question as I recently watched this youtube clip on singing to a key, and it seems certain keys are more suited to your home area, VS keys that make you really stretch to hit the high notes.

http://www.youtube.com/watch?v=d1J36vU-76A

Thanks in advance for any help with this question.

Cheers.