In the Main Menu go to Features. Then go to the Codes menu and enter the following codes.

Code Effect

2ksports Unlocks 2KSports Team
nba2k Unlocks NBA Development Team
payrespect Unlocks the ABA ball
vcteam unlocks Visual Concepts team

Complete each achievement to get the allotted gamerscore.

Unlockables

10 Online Ranked Wins (25) Win 10 online ranked games.
15 Blocks (20) Record 15 blocks or more with any team.
15 Steals (20) Record 15 steals or more with any team.
15 Threes (15) Make 15 three pointers or more with any team.
20 Online Ranked Wins (35) Win 20 online ranked games.
2K Beats Playlist (10) Create a 2K Beats playlist.
3 Online Ranked Streak (15) Win 3 online ranked games in a row.
3-For-All (20) Make at least 10 3pt FG's while shooting at least 45% from 3pt range with any team.
30 Assists (20) Record 30 assists or more with any team.
3pt Shootout (25) Win the 3pt Shootout.
5 Online Ranked Streak (20) Win 5 online ranked games in a row.
5 Online Ranked Wins (15) Win 5 online ranked games.

All-Heart (15) Start the 4th period losing by 10 or more points and win the game with any team.
All-Hustle (15) Record at least 10 offensive rebounds, 5 blocks and 5 steals with any team.
Allen Iverson (25) Record at least 30 points, 10 assists and 5 steals with Allen Iverson.

Carmelo Anthony (25) Record at least 40 points and 8 rebounds with Carmelo Anthony.
Chris Bosh (25) Record at least 30 points, 15 rebounds and 2 blocks with Chris Bosh.
Chris Paul (25) Record at least 25 points, 10 assists and 5 steals with Chris Paul.
Create Player (10) Use the Create Player feature.
Defensive FG% (15) Hold the opposing team's FG% below 40% with any team.
Dwight Howard (25) Record at least 20 points, 15 rebounds and 5 blocks with Dwight Howard.
Dwyane Wade (25) Record at least 30 points, 9 rebounds and 9 assists with Dwyane Wade.

East vs West (15) User controlled team must win this matchup on All-Star difficulty.

Gilbert Arenas (25) Record at least 35 points, 5 steals and 5 threes with Gilbert Arenas.
Good Hands (20) Record 20 assists with no more than 5 turnovers with any team.

Ice Water (15) FT% over 85% with at least 15 FTA's with any team.
Inside Domination (20) Score at least 60 points in the paint with any team.

Kevin Garnett (25) Record at least 25 points, 15 rebounds and 7 assists with Kevin Garnett.
Kobe Bryant (25) Record at least 40 points, 5 rebounds and 5 assists with Kobe Bryant.
Kobe Bryant Dunk-Off (35) Defeat Kobe Bryant in a Dunk-Off.

Lakers vs Clippers (15) User controlled team must win this matchup on All-Star difficulty.
LeBron James (25) Record at least 35 points, 7 rebounds and 7 assists with LeBron James.
Lights Out (15) FG% over 55% for the game [minimum 40 FGA's] with any team.
Lockdown (20) Record at least 10 blocks and 10 steals with any team.

Online Draft League (10) Participate in an online draft.
Online League Game (15) Complete an online league game.
Online Ranked Game (15) Win one online ranked game.
Online Ranked NBA Blacktop Game (15) Win one online ranked NBA Blacktop game.
Online Tournament Game (15) Complete an online tournament game.

Pistons vs Heat (15) User controlled team must win this matchup on All-Star difficulty.

Rebound Margin +7 (20) Win the rebound battle by a margin of +7 with any team.

Second Unit (15) Score at least 40 bench points with any team.
Sprite Slam Dunk (35) Win the Sprite Slam Dunk Contest using LeBron James.
Spurs vs Mavericks (15) User controlled team must win this matchup on All-Star difficulty.
Steve Nash (25) Record at least 20 points and 15 assists with Steve Nash.
Suns vs Lakers (15) User controlled team must win this matchup on All-Star difficulty.
Suns vs Mavericks (15) User controlled team must win this matchup on All-Star difficulty.

Track Meet (15) Score at least 15 fastbreak points with any team.
Trivia (35) Answer 30 trivia questions correctly.

Yao Ming (25) Record at least 30 points, 15 rebounds and 5 blocks with Yao Ming.