Cool, I'm the only vote for TBS.
If I had to pick just one, it'd definitely be Turn-based Strategy. Just a few reasons - X-Com: UFO Defense, Master of Orion, Jagged Alliance, Fantasy General
SRPG would probably be my second, with something like Shining Force, Fire Emblem, or FFT up there.
Although I'm a huge shooter and RTS fan as well, I'd most likely go with some sort of simulation games coming up in third. I think that's what you'd categorize Wing Commander and any space-flight sim as. I think Mechwarrior would fall under action/simulation since it's "giant mech game" rather than a FPS or TPS or RPG or whatever, it blends elements of all of these into one. Racing games could also be filed under simulation, at least some of them (ToCA 3, etc.) and that would encompass even more games instead of me just saying "driving games" as a genre...
But honestly, there's a lot of genres I enjoy, and I would hate to have to just pick one. I'm a varied gamer with a lot of different tastes and a lot of experience, so I'm voting TBS because it's underrepresented and I love it.