iPhone 3G - Cydia Not Working?

[5ABI]

I have an iPhone 3g running iOS 3.1.2, Firmware 5.11.07, Unlocked and Jailbroken. My question is that whenever I try to pull up Cydia it comes up and says "Loading Data" for about 45 seconds and then just crashes. The only application I have from Cydia is Rock and that doesn't even work anymore! So, could anyone please help resolve my issue with Cydia?
Thanks in Advance.

 

[giffut]

Did you jailbreak with redsn0w?

 

[5ABI]

Did you jailbreak with redsn0w?

No, blackra1n.

 

[Applejuiced]

I'd try a restore back to 3.1.2 and then JB with redsnow.
Do not install Rock, its abandoned and dont even work any more.