I definitely think Wrestlemania 26 was better, it had a better build-up if you ask me, and it had a great stipulation that really added to the excitement, and especially to the Shawn Michaels fans it added the saddened feeling that we might (might!) not ever see Shawn Michaels in any association with WWE again, except for a Hall of Fame induction.
Also, just as last year's match-up it had the numerous finishers that made you go "yep, he's done, this is it!" only to add to the excitement once more when one of them successfully kicked out.
The crash on the announce table, plus the tombstone on the outside, the whole, no count out no disqualification thing was a perfect add to it, which made the match so much more magical (thank god there wasn't any weapons involved, cause that's what I feared would ruin the match)
Plus the end of it was brilliantly handled, Shawn pissing off Undertaker only to be punished brutally, and then the handshake and the hug, and the ovation to Shawn was brilliant, he totally deserved the tribute, and I cannot wait till RAW.
So definitely Wrestlemania 26.