"27 year-old computer dude", implies to me that you maybe geographically bound to a certain locale due to your career. If so, the conventional suggestion is to go through the entire phone book and start a list of all the martial arts places that you might like. Narrow down, prioritize the list, and visit every place. But don't stop there. Also be sure to ask everyone you know what other styles are out there and which do they think best fits your criterias.
While just about every style will "keep/get [you] back in shape", only a few is actually good enough for you to "defend [yourself]".
"I want to be a Warrior, Philosopher, statesman" is a noble goal. As painful as it is for me to say this, even fewer schools pursue this avenue.
Other helpful tidbits is to make sure you have a one-on-one chat with every teacher at some point and make sure that you actually like that teacher. If not, no matter how promising the style itself is, cross it off your list. Also, try to avoid long-term commitments. Three months minimum is probably enough to give you an idea of whether you want to spend the rest of your life training in this style or not. Finally, never be afraid to leave for any reason.
You are definitely asking the right question in the right place(s). Some of the people on here are the best in the business. (Oops. "Business" is a bad word.