Improve MS SQL Performance

Hello,
I'm using MS SQL 2008 SP3 as a back end in my performance testing of my web application.
At some point performance degraded and analyses pointed that the bottleneck is my database. I have to improve performance and I'm thinking either 1. update MS SQL 2008 SP with cumulative packs or 2. upgrade it to MS SQL 2008 R2.
Could you please advice if I should expect improve of performance by option 1 or option 2?
Thanks

I would always make sure I run with the newest update.
But I still have my doubt that alone will solve you problem.

What kind of web application do you test? how did you test it?

When do you notice the performance degree? what is "at some point"?
Have you looked at the system itself (e.g. for sufficient RAM) or the queries you use.

Thanks for your reply.
I decided to spend more time in analyzing and tuning my existing db.
I'll run perfmon and etc to narrow down the issue.
thanks