I don't know much about routers and other internet stuff, but it's probably your internet service rather than the router. I guess one way to see would be to hook your computer directly to the modem and do a speed test, and compare it to a speed test of how you normally have it. It also depends on where the server you're connecting to is located compared to where you're at. Again, I don't know much about this stuff, so take it with a grain of salt...
Getting a better connection won't help with ping. Ping is the delay between the data being sent from the server to your machine. A better connection won't help with that. The router may be an issue but probably not. Check your connection to the modem (with Windows just hover your mouse over the icon in the toolbar and it should tell you). If the connection is strong, i.e. full bars, then the modem is not the problem. Most likely you just live in an area that just happens to have bad ping.