Ya, that's still inconclusive. Is your CONNECTION laggy on Graal, or does Graal not run at FULL SPEED(smoothly, 20fps). See, one means Graal is having problems establishing a stable connection, while the other means Graal is having a hard time running on your hardware for whatever reason. They are two completely different problems that need to be approached differently.
The first(actual connection latency) would be evident by slow loading times on Graal and high pings(takes a long time to download a large file from Graal, like a tileset, or taking a while for your connection to communicate with the Graal servers). Most servers have a way to check your ping with them(on Unholy Nation it's 'showlag'), and as for the former... well I'm not sure. I can usually tell what kind of speed I'm getting on a server by watching large files download in the F2, 'files' tab. Alternately, you can go to
http://statistics.graal.us/ and look up your desired server, grab the IP and go to start > run > "cmd" and then type "ping <insert server IP here>" and it will tell you your ping for that server if they don't have a command for it.
As for the latter, actual game slowdown... well this is most apparent by just looking at Graal and seeing if things
visually look sluggish. If worst comes to worst, log on to Unholy Nation and press alt+f, which will bring up my FPS display(f:xx). 20fps is the desired framerate for Graal, and if it's running lower than that during normal gameplay, than something else is going on and it's not your internet connection.