Which is better,cruise or time share rental in Hawaii?

The cruise is 7 nights and costs $4500 including air. However, the time share-townhouse is only $695 for a week(Sat. to Sat.). We have three kids inclu. a 5 yr old and 7 month old. Should we go for the time share? They told us it has a kitchen and restaurants down the street. The beach is very near Wakiki. The cruise will go to different islands but this one is only on one island. First time to Hawaii. Please advice. Also does anyone know where to get cheap tickets to Hawaii? Thanks.