Ok, first I corrected your little spelling error in the title for you. “Which Router is better? Draytek Vigor 2500WE vs. D-Link 624+”
Look that router up on the web and see the reviews on it.
As for your D Link, try updateing the firware and if you’re on a PPPoE connection make sure the MTU is below 1500, I have mine set at 1498 and I’m doing great.