The museum is worth a good few hours, if you are into this sort of thing. It is quite a surprise - almost a tardis - as it looks small from the outside, and yet holds vast quantities of exhibits. It contains everything from carved doors and ancient statues, to sarees and foot scrubbers.
The guides are more than happy to explain the provenance or story behind each item, and if you have time it is extremely worthwhile. Otherwise, it is easy to lose yourself in the wonder and grandeur of it all, and wander around realising that really, some things just haven't changed at all here since the sixteenth century.
For me the musical instrument section was particularly interesting - especially after having just read 'A Suitable Boy' by Vikram Seth (a must before you go to India), as the museum was displaying the sarangi played by the famous Khan.