Thanks again for all of the replies.
After waiting 2 days, I have separated them. The betta never bothered the goldfish, other than the posturing in the initial 10 minutes or so. However, the goldfish would only come out of the corner during feeding time.
The betta is back in the 2 1/2 gallon by himself, and the goldfish is living single in the 29 gallon. I'll be off to the store to get a 10 gallon quarantine tank this weekend. (now I just have to figure out where to put it!)
Thanks again for the advice, I'll post a follow up here to let you guys know how long before the goldfish is back to "normal".