Samsung Galaxy S :: Black Screen Following Firmware Update

I just plugged into Kies and performed a Firmware update, which I assume was the Froyo update. It all ran it's course perfectly and the phone then went to reboot. Following this, it hung on the Galaxy S animated screen before simply going to a black screen (I know the phone is still on, because the two bottom corner buttons will light up if pressed).

I realise that this black screen is quite common, and that people suggest booting into recovery mode. The problem is, I've never been able to get my phone into recovery mode. I turn the phone on and hold down Power + Home + Voume Up for a couple of seconds and then let go... it does nothing, it just goes onto the Vodafone screen and then carries on booting.

I also tried holding down these buttons for a little longer, but all that it does is pushes the phone into a constant restart loop (as obviously I'm holding down the power button).