Flashing it is the right thing to do. If it's too slow for you, just leave your personal data in there.

Flashing is easy. Just download the program from Nokia and follow the instructions.

I figured out exactly when to remove your finger from the home button during flashing, by the way. Watch the screen. When it says it has detected a device, that is the exact moment to remove your finger. For some devices, the timing may not be critical. For mine, it is.