Code Geass is an excellent anime for pretty much anyone. The series does involve Mecha but it's not an overly smothering feature, so if Mechas aren't your thing don't worry about it. Both the anime and manga are good, but I'd suggest watching the program since it covers pretty much everything that's in the mangas anyway. Here's a little about the plot:
Lelouch Lamperouge is an incredibly intelligent young high school student living in future Japan after a great world war in which the country Britainna took over the majority of the planet. Japan, renamed area 11 is under a harsh tyrannic rule with its citizens oppressed. On his way back to to the academy after winning an illegal chess match, Lelouch is accidentally involved in a terrorist operation and shot. He survives by assistance from a mysterious power and some quick thinking. And so begins his epic journey to take the world from the hands of the Emperor and Britannia as revenge for his family.
That's just about as much as I can reveal without spoiling the story. I do recommend this anime to anyone who likes strategy, tactics, total badassery and more. Lelouch is hands down one of the biggest winners ever, I have yet to meet a more smug protagonist. He is more of an anti-hero than anything else.
Overall, don't miss out on Code Geass if you like anime. Sponsored by Bandai, you can tell it's arguably one of the best out there. I can't promise you'll love it like I did, but you will be able appreciate this anime, you'd be mad not to!