Dell Studio 1537 WiFi questions

I have a Dell Studio 1537 and have a few questions regarding the WiFi in this computer. First, installed in the laptop is a Intel WiFi Link 5100 card. When the computer was new, was this the best or worst WiFi card you could get with it. Next, what possible upgrades to the WiFi could I give it? Like maybe, if this is not the best card you could put in it, maybe can I install the best one that it came with? Or preferably, maybe install a newer one that still works with this computer? There seems to be little info on the web(that I can find anyways) about this issue, and I do want to make my computer the best that I can. Thanks to anyone that is willing to help with this.