Computer Hangs/Lags in WoW, here are symptoms

[s37d]

I have a question regarding my FPS in World of Warcraft. It's not so much my fps really, but it will lag or hang in certain areas. For instance when there are many players around me it will often just hang for half a second or so then revert to its normal fps. I don't know whats wrong really, as it should be running smoothly. Heres my stats:
ASUS P4P800S (800FSB) DDR400, 8XAGP, USB2.0, Sound, Lan, S-ATA
Intel Pentium 4 Prescott 3.2 GHz (800 FSB) 1024K
2 gigs(2x1gb) of Patriot DDR400 Ram, timing 2-3-2-5
MSI Geforce FX5900XT 128Mb DDR 8x AGP dual head, VIVO
Sound Blaster Live 5.1 Digital
120.0GB Western Digital 7200RPM UDMA100 8m Cache

This is brand new ram, and I have friends with half that amount of ram who dont have lag issues. I can only assume its my video card. I didn't think the 5900 was that much worse than the higher end geforces, but maybe it is. Was looking at this one: http://www.newegg.com/Product/Product.asp?Item=N82E16814130203

Anyway, my main question is what is causing my computer to hang like this in more demanding areas of the game, and if its my video card, would that card I posted be a guaranteed fix. thanks

 

[Ridlyn]

the problem could lye in ur video card, the rest of your comp is great just need a better video card, if ur low on money i suggest the 6600gt, or the 6800gt if u have more money. The reason not to get the 6800ultra is because u can easily overclock the 6800gt to just as fast as the ultra.

 

[PoisonPorkchop]

Yeah it is most likely your videocard. Get the 6800 GT like ridlyn said. Or if your a rich bastage, a 7800 GTX. But you have agp so NVM

 

[s37d]

Yeah I was a bit curious about the interfaces...if I were to build a new computer a year or so from now, would it be wise to make sure it has pci express x16 or x1 slots? Are these slots faster ins ome way? And do they look like regular pci slots?

 

[PoisonPorkchop]

Well, pcie isnt faster yet, but it will be within the next 2 generations or so. Also, the newer cards arent available in agp. From now on card makers are only making pci-e