All Ethernet can be run a maximum of 100 meters(328feet). The speed is determined by many factors. Most all Ethernet cables are UTP, which stands for Unshielded Twisted Pairs: the twisted construction of the cables provides some shielding and is used to prevent cross-talk between pairs. Actual shielded Ethernet cables are seldom used anymore, due to the high cost and small improvement in shielding. Along with proper grounding to protect your equipment and cabling.
There are basically three Ethernet standards in use.
IEEE 802 3a-100BASE2-10 Mbps
IEEE 802 3u-100BASE2 -TX-100 Mbps(Fast Ethernet)
IEEE 802 3z-1000BASE2 -X-1000 Mbps(Gigabit Ethernet)
Ethernet standards are backwards compatible and all use standard RJ45(8P8C) modular connectors. Most Ethernet connections today are 100Mbps fast Ethernet using UTP CAT5e cable. Gigabit Ethernet is 1000Mbps using CAT6 or CAT5E UTP cables and devices. Ethernet connections are determined by the speed of the port and the cabling. The connection speed will always negotiate at the speed of lowest devices. For example, if you have CAT6 cable Ethernet cable to connect your routers which have Gigabit Ethernet (1000Mbps) ports, and it is connected to an old PC with a 10Mbps NIC then your connection speed would be limited to only 10 Mbps.
In order to achieve Gigabit LAN speeds, all devices in the connections should be Gigabit. This would include the LAN ports on the router, the network interface in the devices and the cable connecting them. You may always mix faster Ethernet cables and devices to slower networks, as stated before the network will default to the slowest link. Remember this is only the Local LAN Speed. Internet(WAN) speed is determined by your ISP. For example, a 3 Mbps internet connection can only provide 3 Mbps even if you connected to a Gigabit LAN networks.
CAT7 Ethernet cable is designed to be used in 10 Gigabit networks, all the equipment would have to support 10 GB speeds. You are unlikely to find the capacity in an affordable range for many years.
With all that being said, I would not want to have to terminate CAT7 or CAT8 shielded cabling it would be a painful experience. It has its place in the hospital or military installations to help protect from interference, but in general not for most common use in building and homes.