Slow speed might possibly have to do with the router, so I would try at least unplugging it for 30ish seconds, then plugging it back in. That probably won't help, but it's worth a try.
If you really need the wifi and it's just unusable in this condition, then I would suggest either replacing the wifi card in the laptop with a different one if that's possible (I looked up your laptop, and I would hazard a guess that it has a regular mini PCI slot (based on the fact that it has DDR RAM, and I've only ever seen mini PCI express slots on laptops with DDR2 RAM), so you would need a mini PCI wifi card if the chip is not built into the motherboard). If the chip is built in, or if you don't know how to find out, the safe way would be to buy a PCMCIA or Card Bus (like
this) (which are really the same as far as I know, so it doesn't matter a whole lot which you buy) wifi card.
Or you could buy a USB wifi adapter (like
this. I have one and it works well), but I find them to stick out rather awkwardly on laptops.
Good luck,
Brijar!!!