1. You should turn off the computer and go to bed now.

2. Ten more minutes, please.
3. Give me ten more minutes, please.
4. Wait ten more minutes, please.
5. __________________________
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#2 is the response to #1.
Does #2 mean #3 or #4 or something else?

Yes, 2 is one answer to 1.

3 also works fine, but 4 sounds more like a command. No child should use this when speaking to his parent!

Maybe these:

May I have ten more minutes, please?
Can I have ten more minutes, please?
Could I have ten more minutes, please?

In this context, #2 refers to asking for ten more minutes before turning off the computer and going to bed. It is similar to option #3 where someone is requesting ten more minutes, but it is different from option #4. In option #4, the person is asking someone to wait for ten more minutes, but it doesn't necessarily mean they are referring to the computer or going to bed. Therefore, in this context, #2 means asking for ten more minutes before turning off the computer and going to bed.