the speeds are correct for 512k broadband, if your just concerned because some of the web pages take a long time to load this may be down to the site you are visiting or simply the number of people online slowing everything down, for a speed test click here
I recently had broadband installed. Speed tests showed it was running as expected, but it still seemed a bit sluggish. I did a clean reinstall of everything, cleaned up unnecessary programs running in the background and increased RAM on my laptop (only had 64MB - Desktop was OK). I also downloaded RAM idle which keeps the RAM free. All this made a real difference to the speed pages display and how quickly IE6 and OE start up. The connection speed is not the only factor.