Not sure if this is what you want, but on your homescreen press the menu button>manage panels>untick everything. 'All' should be ticked by default and you will have a non changing/fixed dock.
Eeerrrr okay, this is weird, why have a OS7 device and want it to be like an older OS5 device? Hehehehehe jus buy a curve 8520 and u'll be sorted bra! *lol*