At the options menu, select the "Cheat Codes" option, then enter one of the following codes to activate the corresponding cheat function:

Dirt Sheet and Vince's Office areas - Enter "BonusBrawl" as a case-sensitive code to unlock the Dirt Sheet and Vince's Office areas.

Bonus Backstage Brawl areas - Successfully complete the indicated task in Road To WrestleMania mode to unlock the corresponding area:

Dirt Sheet: Play as Brand Warfare, and win the handicap match with either Triple H or John Cena in Week 11.
Interview Room: Play as Shawn Michaels, and successfully complete Road To WrestleMania mode.
Locker Room: Play as Edge, and drag Mr. Kennedy on top of the Big Show and count the pinfall at No Way Out.
Vince's Office: Play as a created Superstar, and win your match in Week 6.

Bonus characters - Successfully complete the indicated task in Road To WrestleMania mode to unlock the corresponding character:

Cowboy Bob Orton: Play as Randy Orton, and do not use any strikes in your match in Week 9.
Dusty Rhodes: Play as Randy Orton, and defeat Cody Rhodes at WrestleMania and K.O. Dusty after the match.
Eve: Play as Mickie James, and pin or submit Maryse in Week 2.
Ezekiel Jackson: Play as a created Superstar, and throw each opponent out of the ring at least once in Week 3.
Green and Red Dummies: Play as Randy Orton, and refuse Cody's help, then reverse three of Batista's attacks in Week 3.
Jesse: Play as Edge, and hit every opponent with a finisher in Week 2.
Mr. McMahon: Play as Edge, and put Triple H through an announcer table in Week 11.
"The Million Dollar Man" Ted DiBiase: Play as Randy Orton, and defeat Ted DiBiase Jr. at WrestleMania and K.O. "The Million Dollar Man" after the match.
The Rock: Play as Edge, and successfully complete Road To WrestleMania mode.
Trish Stratus: Play as Mickie James, and successfully complete Road To WrestleMania mode.

Alternate attire - Successfully complete the indicated task in Road To WrestleMania mode to unlock the corresponding character's alternate attire:

Chris Jericho: Play as HBK, and make Jericho bleed in Week 6.
Edge: Play as Edge, and win in under three minutes in Week 6.
JBL: Play as HBK, and win the match in under four minutes in Week 8.
Mickie James: Play as Mickie James, and defeat Michelle McCool in under three minutes in Week 6.
Mr. Kennedy: Play as Edge, and eliminate Mr. Kennedy from the Royal Rumble match.
Mr. McMahon (suit): Play as a created Superstar, and spend at least one minute of the match outside the ring in Week 5.
Natalya: Play as Mickie James, and choose Kendrick over Natalya in Week 9. Then, win the match while suffering minimal damage in Week 10.
Santino Marella (street clothes): Play as a created Superstar, and make a successful diving attack from the top of the ladder in Week 12.
Shawn Michaels: Play as HBK, and hit both opponents with Sweet CHIN Music in Week 4.
Shawn Michaels (DX Option 1): Play as HBK, and accept the Retirement Match in Week 10. Then, have your partner be the legal man longer in Week 11.
Shawn Michaels (DX Option 2): Play as HBK, and decline the Retirement Match in Week 10. Then, execute three Double Team attacks in Week 11.
The Brian Kendrick: Play as Mickie James, and choose Natalya over Kendrick in Week 9. Then, win the match without using a signature move or finisher in Week 12.
Vince McMahon (chicken head): Play as a created Superstar, and win the WrestleMania match.
Miz and Morrison (street clothes): Play as Brand Warfare, and win the handicap match with either Triple H or John Cena in Week 11.
John Cena (street clothes): Play as Brand Warfare, and put Kane through a table in less than 2:30 with John Cena in Week 4.
Randy Orton: Play as Randy Orton, and R.K.O. Dusty Rhodes at No Way Out.
Triple H (DX): Play as Brand Warfare, and win your match in under three minutes with Triple H in Week 6.

Extra Road To WrestleMania unlockables - Successfully complete the indicated task in Road To WrestleMania mode to unlock the corresponding bonus:

Champion Of Champions title belt: Play as Brand Warfare, and win at WrestleMania.
DX, Morrison, The Hardys, and The Miz tag entrances: Play as Brand Warfar, and win the Battle Royal with Triple H or John Cena in Week 2.
Road To WrestleMania Event Skip feature: Play as Randy Orton, and spend less than two minutes in the ring with the legal Superstar in Week 12.
Santino Marella Story Designer story: Play as a created Superstar, and reach 500 degrees at least four times in Week 11.

Extra abilities - Successfully complete the indicated task to unlock the corresponding ability in Create-A-Superstar mode. To assign them, select "Abilities", then choose "Create-A-Moveset".

Durability: Get your Durability score to 85.
Exploder Tunbuckle Attack: Get your Speed score to 75.
Fan Favorite: Get your Charisma score to 80.
Fired Up: Get your Overall rating to 90.
Hardcore Ressurrection: Get your Hardcore score to 90.
Kip Up: Get your Technical score to 85.
Lock Pick: Get your Submission score to 80.
Object Specialist: Get your Hardcore score to 70.
Resiliency: Get your Overall rating to 92.
Strong Strike: Get your Strike score to 75.

Trophies - Successfully complete one of the following tasks to get a trophy:

Story Designer (Bronze): Create an original story using WWE Story Designer Mode.
Face on the Big Screen (Bronze): Convert a Highlight Reel into an entrance movie.
Check Out the New Threads (Bronze): Create Alternate Attire for a Created Superstar and new Threads for a WWE Superstar.
A Showman Like No Other (Silver): Have a total of 20 or more 5-star rated matches in your overall match history.
Mickie James Story (Silver): Complete the Mickie James story in Road To Wrestlemania mode.
Edge Story (Silver): Complete the Edge story in Road To Wrestlemania mode.
HBK Story (Silver): Complete the HBK story in Road To Wrestlemania mode.
Orton Story (Silver): Complete the Orton story in Road To Wrestlemania mode.
Brand Warfare (Silver): Complete the Brand Warfare story in Road To Wrestlemania mode.
Created Superstar Story (Silver): Complete the Create A Superstar story in Road To Wrestlemania mode.
Developmental Graduate (Silver): Complete the Training Checklist.
Career Growth (Silver): Increase the overall rating of a Created Superstar to a 90 or above.
Finisher of the Year Candidate (Silver): Create a dive finisher, in Create A Finisher mode, and use it in a match (single player only).
Ask Him Ref! (Silver): Win 10 matches by submission (single player only).
Ahead of the Pack (Silver): Win as tentative Champion from start to end in Championship Scramble. (single player only)
Shoulders to the Mat (Silver): Win 50 matches by pinfall (single player only).
A Grappling Machine (Silver): In one match, perform all 16 Strong Grapple moves on your opponent (single player only).
2010 Hall of Fame Nominee (Gold): Induct a Superstar into the Hall Of Fame.
Nothing More to Collect (Gold): Unlock all the playable characters and bonus items.
Royal Rumble Specialist (Gold): Win a 30-man Royal Rumble as the first entrant without changing Superstars (single player only).
And STILL Champion... (Gold): Defend a Title in a Championship Scramble match on Legend difficulty (single player only).
PLATINUM (Platinum): Obtain all other trophies.

Additionally, there are four secret trophies:

New Superstar Initiative (Bronze): Create a Superstar in Create-A-Superstar mode.
An Original Design (Bronze): Create an original image using the Paint Tool.
Intermediate Technician (Silver): Succeed at a cumulative total of 50 reversals (single player only).
Technical Wizardry (Gold): Succeed at a cumulative total of 100 reversals (single player only).