You'll need from the donor car:
C20XE engine, drive shafts (including CV joints), radiator, ECU, gearbox selector and linkage, all pipes and hoses, starter motor, alternator and ignition coil and the engine mounts.
You can also take:
F20 Close ratio sports gearbox, air box (possibly won't fit the corsa engine bay), anti roll bar and manifold.
SFi airbox (on top of the throttle body) might not fit, so you'll have to shave the bulkhead a bit, or buy a Mantzel Powercap (or get one off the Calibra/Cav turbo they're basically the same). Airbox is dubious (if you want a panel filter), but you'll prob want to hear induction??
You will need to modify two of the engine mounts, one is too low, and the other need a new hole drilling in, or buy new mounts from MTech.
Driveshafts need to be modified. They'll fit the gearbox end, but won't fit the less splined hubs.
You could change the brakes and hubs to GTE/GSi ones, but the driveshafts will need to be chopped, shortened and welding back together.
As a rule, take everything from the engine bay, even the clips.
You can go all the way and add traction control and cruise control, just to be unique. Or go turbo and possibly kill yourself by going a bit too far.