Is this a decent resort? I got it for $234 a night all-inclusive with the Divi Aruba.

We too are very hopefully since we are staying there for the first time in December. There are some great reports here:
Inquiring about the Tamarijn (sp)
TAM (updated pictures)
Tamarijn from 6/30 - 7/7

Aruba Bound! ~ Hoosier Kitties ~ Our-Cruises ~ Blogging to Aruba
When Will Dh Take Me Back to Aruba?

What dates are you going in Dec?

Aruba Bound! ~ Hoosier Kitties ~ Our-Cruises ~ Blogging to Aruba
When Will Dh Take Me Back to Aruba?

Dec. 3 - 12. I hope it's a good time! Do you know if they allow a 7 yr. old to go on a jetski with an adult?

I am sure you will enjoy Aruba and the Tamarijn. It is not a 5 star resort, but IMHO, knowing what I know about the resort, with the price you paid, I believe you are getting a very good value.

I am not sure about rules regarding jet-skis, but I did find this post for you. http://www.aruba.com/forum/f8/jetskies-27611/#post93484

Aruba Bound! ~ Hoosier Kitties ~ Our-Cruises ~ Blogging to Aruba
When Will Dh Take Me Back to Aruba?

Yes, a 7 yr. old can go on as jetski with an adult. You have to go up to Eagle Beach to get them. None in front of the Tamarijn. Take the bus round trip for $2.30 each. Kids may be less, not sure. I sent you a private message on the Divi/Tam.

Depending on how fit you are - Eagle Beach is only a 15-20 minute walk up the beach from the Tamarijjn (or however you spell that). We are at Divi Dutch Village right next to it and I walk up to the motor sports at Eagle Beach each morning and back.