hi- we are looking to go to the Westin Our Lucaya Beach from Sept.17-22 - does anyone know the weather at that time and can recomend going there?

We've been there during the month of September (actually end of September/beginning of October). It was hot during the day. The evenings were really nice/comfortable (maybe low 70s). And it didn't rain. We liked the Westin.

would you recomend going during that time or another one?

I'm not sure what exactly you're looking for/concerned about. Weather? Crowds? I can tell you that I thought the weather was perfect and there was barely anyone at the resort when we went (which we loved). So for those 2 reasons, yes you can go at that time.
We went in 2003 so our trip was not that recent. When we were there, the beach was just lovely with clear, calm, clear blue water. The island has been hit a couple of times with hurricanes since. I'm not sure how the beach has fared. I'm sure there are recent trip reports on Trip Advisor.
By the way, our favorite part of the hotel was the infinity pool that's all the way on the left side (when you're facing the ocean). There was barely anyone at that pool. They also have a swimup bar but the water there was ridiculously warm. eewwww... Let's just say we got it and got out right away.
There's a market with small stores and restaurants right across the street. Great place to buy souvenirs and grab food other than hotel food (cheaper too).

Weather is full-bore summer, but it is also peak hurricane season.

i thought hurrican season woul dbe over by then...

The Atlantic Hurricane Season runs from June 1 through November 30. September is peak storm season.

Got to the following websites for historical weather info.:
http://stormcarib.com/
http://www.wunderground.com/tropical/
http://www.weatherbase.com/

there goes the carribean...

There are caribbean islands that have a much lower chance of hurrican--Aruba, Curacao, Bonaire. Because they are so far south, they are almost outside the hurricane belt (while it is still possible for them to get hurricanes, it is very rare). If you have your heart set on Caribbean, you should check those islands out. I really enjoy Aruba, and Bonaire and Curacao have many fans as well.

I am also pretty sure that Sept. is the middle of the hurricane season. That said we have been to the Bahamahas and the Virgin Islands in July and Aug, in the 1990's and never hit more than a day of rain and no where near a hurricane,
But with global warming the past 8-9 years all bets are off in that and other regions. Even Bonaire which was know to always be out of the hurricane belt got blasted 7 or so years ago.The Cayman's also got blasted twice in 3 years. So, it is risky. Late Oct in the Eastern caribbean to middle Caribbean still hs lower rates and less chance of hurricanes.