Greetings Loki:
I'm afraid it's bad news. Laptop GPUs are soldered onto the motherboard (as is the CPU), leaving users with only the option of upgrading the RAM and the HDD (and sometimes not even the RAM). I assume you have the 1.5 GB GTX460M which is a bit on the low end, as you said.
What OS are you running? You might be able to squeeze out some speed by upgrading to 64-bit and re-download all graphics drivers in 64-bit version. This would only offer a mildly improved viewing experience and has nothing to do with the GPU itself.
Other than that, you'll have to get a new laptop.
Best of luck,
GreyCatz.