I have read loads of articles on ideas for Wrestlemania 25 and not liked many, idea's of Orton vs Cena again and HHH vs Edge again. I think I can do a better job, so here goes.
Jeff Hardy vs Matt Hardy (or Shawn Michaels, can't decide)
Michaels wins the Rumble eliminating Matt Hardy or vice versa
John Cena vs The Undertaker (title vs streak)
The Undertaker wins elimination chamber match at No Way Out
Edge vs Christian
Hogan vs Austin
Hogan challenges Austin at the Royal Rumble, Austin declines. Stone Cold wants to win the Rumble and retire the champ. Hogan either eliminates Austin or costs him the match.
Austin is outraged and attacks Hogan. At the next RAW, Austin accepts the match. Over the next few weeks, Austin is crazy beating everyone he can, smashing everyone in his way. We see Hulk talking about his recent problems, and his family begging him not to fight because Stone Cold is maniacal
MITB the next generation Randy Orton vs Ted Dibase vs Cody Rhodes vs Sim Snuka vs Manu vs DH Smith
During an episode of RAW, legacy are arguing who is going to be the next big thing. Vince McMahon comes on screen and says to answer it they can all fight at Wrestlemania 25. Over the weeks leading to Wrestlemania no one knows who on who's side
Edge vs Christian
Christian cost Edge the title at the Royal Rumble and pins him at No Way Out in the elimination Chamber.
Steph vs Shane McMahon
Vince gets involved, backing Shane, HHH backs Steph, JBL backs shane. At Wrestlemania, Shawn must chose his employer or HHH.
Shelton vs Shawn Michaels in interbrand iron man 30 mins (non title)
Carlito and primo vs John Morrison and the miz
HHH vs Mr Kennedy
CM Punk or William Reagal vs MVP Last chance title or fired match