Prep iPhone 3G for Sale

Just received my brand new iPhone 3GS and will be selling my Pwnage unlocked iPhone 3G. I was wondering how to prepare the phone to sell it? Here are my questions.

1. Pwnage unlock it with no data from iTunes or my phone #.
2. Securely erase my private data so it cannot be recovered with software.
3. Remove my name from the Apple registration under the iPhone serial #.

Anyone with experience with these matters, I would appreciate any advice you may have!

Thanks,
HL

So following a forum user's instructions I went to Settings > General > Reset > Erase All Content and Settings. The warning said it would take 2 hours but it seems like 3 or 4 hours have passed already. All I see is black screen with the white Apple symbol? Is this normal? It seems like it's resetting some process every now and then. Perhaps I should have just restored using the custom firmware...

I know, I know, I screwed up!

So what should I do? Should I let it run a few more hours just in case? Or should to restore a custom firmware to it? Hold power and home button to reset?

I DFU restored with the help of Pwnage, opened iTunes and option restored a custom firmware I created previously. Just finished ultrasn0w unlock and all systems are GO! Thank you again!

I turned on my phone this morning and had no cell signal. Sometimes I will get no signal at all and my only solution is to put my iPhone 3G into airplane mode on and then off, then the signal will come back. Is this normal? Or do I have to update my ultrasn0w unlock or Cydia packages? I jailbreaked using Pwnage v3.1.4. I don't understand anything about Cydia and updating it so I listed all my installed packages. Thanks!

-iPhone 3G firmware 3.1.2 (7D11)
-Cydia Installer 1.0.3172-68...
-ultrasn0w 0.92
-BigBoss's Source 0-12
-Cydia Community Sources 0-10
-Dev-Team 0-3
-iSpazio 0-5
-ModMyi.com 0-5
-OpenSSH 5.2p1-8
-Saurik's Source 0-4
-ZodTTD's Source 0-4