If your computer will have only one hard drive, because you are replacing not adding a drive, then I suggest you stay with IDE. The motherboard in your computer is likely not to support booting from a SATA drive.
It is also very likely that your computer does not now have any SATA controllers, making it impossible to connect a SATA drive unless you add a SATA controller card to an available expansion slot.
This would depend on the motherboard. If it has the SATA ports on the board, then more likely than not it will boot from them just fine. I've got two motherboards with an IDE port and several SATA ports, and it'll boot fine from either the IDE or the SATA channel. At the worst, you might need to slightly alter a BIOS setting to ensure the SATA device is listed under the bootable devices.
I'm not sure how booting would work with an SATA controller card, as I've never actually installed one.
I've never heard of a board that has the SATA channels onboard but won't support booting from them. That would imply that they aren't properly recognized by the BIOS (which should generaly recognize bootable devices on all the IDE channels, the SATA channels, the floppy channel, and possible the USB ports), which I would think is a Very Bad Thing
TM.
Anyway, as the OP's question, it would depend on what your current situation is. If you have the SATA channels, you might as well get an SATA drive. They're common, no more expensive than the IDE interface, and offer increased performance over the IDE interface. Moreover, the cables are less of a pain in the ass to run inside the box.
If you're happy with the IDE, then don't sweat it.
What model motherboard do you have, anyway?
