I have had the same problem with THREE Samsung phones!
2 SCH-u740's and a previous model.

Verizon did the same thing with me -- updated the software at the store, etc. But the problem kept recurring and no one knew the answer.

To prevent an event from recurring over and over even though it does not show up in your calendar anymore (after it alerts you the first time), do NOT change the dafault end time of the event.
For example, if you set the Start Time for 1PM, the phone will automatically default the End Time to 1:30PM. Do NOT change the End Time to some other time like 2PM.

I hated to switch to the new Samsung Alias as I don't like "new and improved" interface, so I am glad this fix has worked.
Please post to this thread if this fix works for you.