I'll assume you are eating after the 6pm show. However, my suggestion could work even if it were after the 9pm show.
House of Blues usually has a dining room band starting around 10pm. Just dine, no extra charge for the entertainment. The food is good, not great, but the additional entertainment can be very good.
Visit hob.com and select the Orlando location to see show for your date.
If its during warm weather months, the "Porch entertainer" may also be of interest.