The latter two are not compatible - Socket G2 and Socket G1 will only work together if you happen to have a laptop with a PGA989 that has an extra pinhole which can accommodate both these lines of CPU.
You might be able to use other Westmere mobile CPUs, but it's a gamble because laptops aren't known for having BIOS that will accept all technically feasible mobile CPUs. I wouldn't bet heavily on something like an i7-640M working. You're also not going to have a huge chance in performance; it'll be faster, but in this generation, going up to i5/i7 only got you boost behaviors, not additional cores of threads.