Change IP address

C:\>netsh int ip set addr local dhcp
C:\>netsh int ip set addr NIC1 static 192.168.1.10 255.255.255.0 192.168.1.1 1
C:\>netsh int ip set addr "Local Area Connection 5" dhcp

The first one works if the connection you want to configure is "Local Area Connection," and they may also work if you have "Local Area Connection 2," but no others. If you're going to use this command on your own PCs with multiple NICs, it'd be better to rename your connections to "NIC1," "NIC2," etc, in which case you can use the second example. If you have multiple "Local Area Connections," you'll have to use the third one with the quotes.

Also note with the static address definition, it should be obvious that the format is IP[space]netmask[space]gateway, but you may not have noticed the [space]gateway metric at the end. To be perfectly honest, I don't even know what this means; just put a 1.

Ping a range of IPs

C:\>for /l %i in (1,1,254) do @ping 192.168.1.%i -n 1 -w 100 | find "Reply"

This will ping all addresses from 192.168.1.1 to 192.168.1.254 one time each, wait 100ms for a reply (more than enough time on a local network) and show only the addresses that replied.

Syntax for FOR /L is (start,step,end) if you want to change the range.

Also, note that the Windows FIND is case sensitive, so make sure you capitalize "Reply," or else use the /i switch or just "eply."