Drury:

There is no technology on earth that can absolutely guarantee a thumbs up from our resident spelling inspector.

It is possible to export the text of each card to your Word spell checker, fix it, and then paste it back, but this would be too cumbersome.

There is, however, a relatively inexpensive spell checker that can automatically attach itself to HyperCard and beep (or honk) at you when you misspell a word (in fact, I just misspelled "misspell" and my little friend beeped at me, suggested a correct spelling, and then retyped the word for me!).

The Thunder II Spellchecker is available from MacConnection for $49 plus $3 shipping.