Powering an arduino mini pro.

I have an arduino mini pro 5V and also have an old cell phone charger that is supposed to output 5v. I just don't know if it is considered regulated.

Do I hook it to Vcc or to RAW?

Measure the charger output with nothing connected - is it 5V?
Measure the output using AC voltage on your multimeter - is there a lot of AC ripple? Or is it measuring very little?
If 5V and little AC, you can connect to Vcc.

5.5v dc and 0.2v ac

Should be OK then.

You can drop it a bit with a series diode if the 5.5V worries you.