I come down in favour of CSI and NCIS, the science is fascinating to me.
I did watch the early L&W series, but as much as I respect John Grisham for his writing, law stories to me are too dry.
Yes, I am a Kate Todd fan and it took me a while to warm to Ziva, when it was Kate and Tony they had the Mulder & Scully thing working-and didn't it go well.
Similar to Mark & Rachel in my Chronicles series http://www.amazon.com/dp/B008BEDMSO / http://www.amazon.com/dp/B009M82G5S
I don't have a favourite CSI series, I think each bring something new to the scenes pertinent to their city. One of the things about L&W is the crime changes, but the procedures can be moved to any city-the law is the law.
I do have favourite ladies in each series though- Marge, Stella and Natalia.
In the debate about Jenny-for me it is long hair-I have a thing about hair.
I can't vouch for JAG as I haven't seen the series, other than the two episodes-"Ice Queen" & "Meltdown-" which introduced a pre-Kate Todd NCIS team.
I think I could enjoy NCIS:LA but for now I have to watch my box sets of NCIS & CSI :)