Well, I just realized that you are doing this on a laptop. And you cannot upgrade to a graphics card on a laptop. And if you are doing all of this on a laptop, you are going to have to do one of the two:
1. Get a better laptop (not recommended); or
2. Buy a desktop PC
The desktop PC is your best option. I'm assuming you don't know how to build PCs, so my advice is to find a buddy that you trust and have him build one for you. Or you can find a computer/PC shop in your area and have them build one for you. You can get a pretty decent desktop for under $1000. My specs, and I built this myself for under $1000:
AMD 64 X2 5600+ 2.8 GHz (dual core processor)
ASUS GeForce 5500 512 MB SLI Ready graphics card (the weak link in my machine)
2 GB Crucial Technology RAM - with heatsinks
2 80 GB Western Digital HDDs
1 20 GB Western Digital HDD
1 external HDD enclosure (I have space issues)
1 ASUS A8N-SLI Deluxe motherboard
1 Broadcom Corp PC Tower w/550 watt power supply
Windows XP Media Center
1 Thermaltake CL-P0114 Big Typhoon CPU Fan/Heatsink
This isn't the greatest machine, but it really works. Less than $1000, and I have found only 1 game that I cannot run on it - COD4. And that's just cuz I need to upgrade my graphics card. You will notice I didn't put any sound in there - I had an old POS sound card lying around and it works fine.