Comment These are some big IFs (Score 4, Interesting) 420
Even if the planets are inside the habitable zone, they would need to be the correct consistencies... Venus and Mars are in the zone here, but neither has life or is natively habitable. Yes, we're attempting to discover if Mars may have HAD life, but as far as we can obviously tell, it has none now...
So it's fun and interesting to search these types of star systems and planets--and I think it's absolutely worthwhile to focus a SETI program on them to try to determine if there are any stray signals we can pick up--but otherwise this really is not much more than dreaming and guessing.
Assuming SETI finds no signals, but we do believe there a couple of planets into the habitable zone, then I think it would make some sense to attempt a probe mission there... but it could be a while before we're at the technology level we'd need...
I think our current speed record in space is about 150,000mph
We'd need something capable of:
a) Traveling at least 1/3rd the speed of light (roughly a quarter billion miles per hour)
b) A power source capable of lasting at least ~40 years or more with enough juice available near end of life to complete its mission
c) Capable of complete autonomy in 100% unknown situation
d) Possibly requiring the ability to actively correct its course en route, and maybe even detect and avoid collisions