Easy I'd take the 2013, they seem to be the more complete team with better depth.
The 2005 defense was a bend but don't break outfit. IIRC Seattle lead the league in sacks. Had it not been for that Seattle would have been very average on defense. In contrast the 2013 defense returns virtually everyone of consequence and upgrades to most of those that left ie ( Trufaunt for WInfield, Avril & Bennett vs. Jones). The 2012 defense was the #1 ranked defense in points allowed #4 in yards allowed. This is the first time since I've followed the Seahawks (since 2003) that Seattle has a bona fide arse kicker of a defense. Before I was a Seahawks fan I followed the Tampa Bay Bucs when they had the stingiest defense around. Seattle's 2013 defense has the ability to reach close to those heights IMO.
Meanwhile the 2005 offense was great when it was clicking. But it wasn't dominant per se. I remember even that year being infuriated at the inconsistencies of the Seahawks offense. Other's teams could drive at will, SEattle at times was hot or cold. If you remember that EPIC game against the Giants when we won in OT after their kicker missed 3 FG's. We'll late in that game and in OT, Seattle struggle to get a single first down. That's how it seemed in 2005, when it was on, it was amazing, when it struggled it really had a hard time moving the ball.
Examples we lost to the Jaguars in week 1 and Washington im week 4. Both of which should have been W's against lesser teams, instead the offense was held in check the entire time. The only reason we beat the Rams on the road was due to a punt recover to ice the game. If you recall the 49ers game on the road. Seattle allowed a HORRIBLE 49ers team to come back and was within a 2 point conversion from tieing the game.
My point is the 2005 team was a great memory, but there were significant holes in that squad on BOTH offense and defense. I think that the 2013 squad is a more sound football team. With better talent on defense and on offense in the passing game for 2013 over 2005.
I'd take 2013- Rice, Harvin, Tate, Baldwin & Miller, McCoy vs 2005- Ingram, Juravicious, Jackson, J.Stevens
I'd take 2013- Unger vs 2005- Tobeck
Obviously - 2005- Jones, Hutch, vs Okung, Carp.
Right side is a wash as both teams have adaquate but not great right sides.
I'd take the combination of 2013- Lynch, Turbin, Robinson, Vs- Alexander, Morris, Strong.
Strong and Robinson are a wash. Alexander beats out Lynch barely. Turbin is a much more gifted player than Morris.
On defense it's not very fair:
I'd take Wagner and KJ over Tatupu and DD Lewis or Jaime Sharper.
Sherm, Browner, Kam, Earl > Significant advantage over 2005 squad of Boulware, Hamlin, Trufaunt, Herndon, M.Manuel
2005 has the advantage on the DL over the 2013 squad.