One of the many perks of a new router is they can simultaneously operate on two separate bands - the older 2.4GHz band as well as the faster 5GHz band.
The 5GHz band is less prone to interference from other Wi-Fi networks and Bluetooth signals, which makes it more suitable for streaming and gaming. Some of your newer gadgets can probably operate on this band.
If your router already supports 802.11n, you might want to make sure your router's firmware is up to date. Instructions for checking the firmware will be in your router manual.
Firmware is like your router's operating system. Most updates fix minor bugs, but sometimes a major update significantly boosts performance or offers features that didn't exist when the router was first sold.