1. You only normally need to nat if you have overlapping IPs or PAT if you want to conserve public IPs.
2.
access-list no_nat_2_dmz permit ip 10.10.10.0 255.255.255.224 30.30.30.0 255.255.255.0
access-list no_nat_2_Inside permit ip 30.30.30.0 255.255.255.0 10.10.10.0 255.255.255.224
static (Inside,DMZ) 10.10.10.0 10.10.10.0 netmask 255.255.255.224
nat (Inside) 0 access-list no_nat_2_dmz
nat (DMZ) 0 access-list no_nat_2_Inside
or something to that effect. nat with a number of 0 does not nat those IPs stated in the access-list that you specify.
The static command allows your DMZ to access your Inside network. You probably want to specify certain IPs and services in static commands instead of just globbing everything together and allowing it. This command works, but kinda defeats one of the purposes of a DMZ.
Note that the nat commands aren't even needed if you don't have :
global (Inside)
global (DMZ)
as the global commands are needed to NAT