I've been to the IHS quite a few times and I think you have to know what you want to see/do before you go.
Exhibits -
It is an interactive history museum, so prepare yourself to "get involved" with actors. I have seen guests come into the building who do not want to have anything to do with the interactive part, which might have turned them away from the exhibits. I would say it's OK for kids who are older, but maybe not as fun as Conner Prairie. I would say the exhibits are geared more towards adults. Cole Porter room is fun, if you are there while a singer is in the room. The IHS tends to have alot of promotions, so I would check local papers for coupons to get a discount off admission. The ICVA might even offer a coupon.
Dining-
The Stardust Cafe is a great place to have lunch during your visit. You can eat on the beautiful terrace outside by the canal or under the starlit ceiling inside. Hoaglin operates the cafe and the food is pretty good - just very expensive! If you park at the IHS you can get your parking validated through the cafe.
Concerts on the Canal -
Their summer concert series is fun, so I recommend this to any locals or visiting families. You can either reserve a table on the terrace (where the band is) or there is free seating on the stairs and the hill across the canal. If you want to sit on the stairs, make sure to get there early - there are always early birds. You can still hear the band from the hill, but boy is it hot!! There is no shade on the hill.
Meetings/Events-
For the location and the ammenities, IHS offers a great deal for meetings and events. Their meeting rooms are equipped with projectors and your guests get free admission to the museum for day time events. My only compaint for daytime meetings is the price of catering - but I guess that's to be expected. The theater is beautiful too and Lilly Hall is only available for evening events.
Hope you enjoy your visit to the IHS!
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.