huh, that's a new one. I'll have to look into that. when you say that the emulators won't run, do you mean that you can't get to the rom list for each emulator? or do you mean that when you select a game it, the emulator itself won't run?
In either case, you can get back to sorting by title by editing the database: 1) on a computer on the same network as your pi, type in the ip address of your pi into a browser. 2) select database admin at the top 3) select options on the left 4) click the little pencil icon to edit the options 5) under Sort Roms by: change it to title (all lowercase) 6) click submit 7) restart piplay
just follow the above directions and that should fix it. somewhere in the database there must be some un-parsable date entry. I have added a fix that will bypass it in the next update.