Need help going BACK to 1.5

[veedubguru]

Have a problem here. Updated Moment with the official Sprint 2.1 update and it has been working HORRIBLY ever since.

Need to know how to get it back to the 1.5 Android it came with.

Now keep in mind I know absolutely nothing about Android. I'm a WinMo guy and this is the wife's phone. I told her there was an update out and now that I've put it on the phone screws up all the time and she's asking me to put it back the way it was.

Got the phone 4 weeks ago, updated it last week using the official update utility. Haven't done ANYTHING else to it.

PLEASE HELP GUYS! I know this has to be possible...