Right I have had a on going problem with my drivers door.

The faults are

When I unlock the car and open the drivers door the rest of the car re locks after about 20 seconds. With the drivers door still open.

The interior light doesn't work when the drivers door is open but it will work when it is just pushed on the catch, not fully shut?

What could be causing this problem and what can I do to fix it

Microswitch in the door i think

Yep, sounds like microswitch. I need to do mine but seems like a pig of a job so have been putting it off

 

guide here http://www.briskoda.net/forums/topic/126257-octavia-1-replacing-door-latch-microswitch/