Wirelessly posted (HTC Diamond: Mozilla/4.0 (compatible; MSIE 6.0; Windows CE; IEMobile 7.11) Sprint MP6950SP)
I suggest you download and flash the shipped rom for your carrier and flash it at least twice. Then clear storage. Then if you want to go back to a custom rom then do so. Use a utility like ClearTemp to help clean out Temporary files at least twice a week and use CleanRam when you want to close processes and free up ram to avoid soft resets if your device is running slow. WinMo has a learning curve but if you are smart enough it is still a powerful platform.