UPDATED 6/16/2016 Thanks for the comments!

Here’s a nice quick script to list all DNS records in each zone on the DNS server(includes sub-zones):

From the DNS Server

$Zones = @(Get-DnsServerZone)
ForEach ($Zone in $Zones) {
	Write-Host "`n$($Zone.ZoneName)" -ForegroundColor "Green"
	$Zone | Get-DnsServerResourceRecord
}

From a Remote DNS Server

$DNSServer = "servernameOrIp"
$Zones = @(Get-DnsServerZone -ComputerName $DNSServer)
ForEach ($Zone in $Zones) {
	Write-Host "`n$($Zone.ZoneName)" -ForegroundColor "Green"
	$Zone | Get-DnsServerResourceRecord -ComputerName $DNSServer
}

From a Remote DNS Server (Output to Tab Delimited File)

$DNSServer = "servernameOrIp"
$Zones = @(Get-DnsServerZone -ComputerName $DNSServer)
ForEach ($Zone in $Zones) {
	Write-Host "`n$($Zone.ZoneName)" -ForegroundColor "Green"
	$Results = $Zone | Get-DnsServerResourceRecord -ComputerName $DNSServer
	echo $Results > "$($Zone.ZoneName).txt"
}