This sounds like Space Quest. Have a look at this excerpt from a walkthrough and see if it sounds familiar:
"After escaping the Arcada before its destruction you crash land on the planet Kerona. Before you do anything “take off seatbelt”. Look at the pod and “take kit”. This is your survival kit. Look kit and you will find an Xenon army knife and dehydrated water.
“Get out” and walk to the front of the pod. “Take glass”. This is reflective glass that we’ll need later on.
Walk to the right three screens and then take the path that leads up. Follow the path all the way around over a bridge that will crack as you walk on it. A spider droid will drop to the ground at some stage. Just ignore it for now. There are two pillars at the end of the path. Stand between them and you’ll be lowered into the earth by a secret elevator."
This sounds like Space Quest. Have a look at this excerpt from a walkthrough and see if it sounds familiar:
"After escaping the Arcada before its destruction you crash land on the planet Kerona. Before you do anything “take off seatbelt”. Look at the pod and “take kit”. This is your survival kit. Look kit and you will find an Xenon army knife and dehydrated water.
“Get out” and walk to the front of the pod. “Take glass”. This is reflective glass that we’ll need later on.
Walk to the right three screens and then take the path that leads up. Follow the path all the way around over a bridge that will crack as you walk on it. A spider droid will drop to the ground at some stage. Just ignore it for now. There are two pillars at the end of the path. Stand between them and you’ll be lowered into the earth by a secret elevator."
Check out some screenshots along w/ the rest of the walkthrough here: http://gamerwalkthroughs.com/space-quest-1-walkthrough-the-sarien-encounter/