eagle7911,
I am so sorry for the issues you are having with your Samsung Fascinate after updating the software! I actually have the same model device, and the update did make improvements on my phone. And it is working just fine now.
This may be due to an application that either didn't close or reinstall properly after the update. I would like to make one suggestion that should allow your phone to work back at an acceptable performance. Performing a Hard Reset will clear any corruption on the device internal memory. I will include a link with instructions and screen shots below. Just ensure you backup your data prior to the reset.
Hard Reset - Samsung Fascinate SCH-I500
Hope this works out for you!
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