I don't feel like cooking tonight. *We will get* a takeaway?
I don't feel like cooking tonight. *Shall we get* a takeaway?
I'll look at your computer when I *have* a moment.
Correct
If the film *is to start* at 8, we'd better get there by 7.30.
If the film *starts* at 8, we'd better get there by 7.30.