#The posed question is about AFTER landing the new planet...#
In the given scenario, we're limited by "current technology" and we need to travel by 500 years. Even if ship crew is safe, the earth changed (yet live?!), so back to earth is worthless.
And it was said all needed resources are supplied by the ship.
So, next steps:
1. Mix up (over power?) with local life forms;
2. Create hybrids (dress up?) with local life forms, especially the intelligent ones.
We need mix up with new life forms, if they're "intelligent" or we can dominate them, if they're "not intelligent".
Best way to profit new environment resources is some type of mutation (actually some thing expected after so many years traveling in space, even in cryogenic).