I couldn't stay away from working on the Disco and thank you for the quick reply DiscoMike!!! OK, now that I'm in a better mood. All the symptoms WERE as follows:
1: Upon cold start throttle would have no response for up to 30 seconds
2: Rough idle with random misses
3: Popping sounds coming from inside the intake, sounded like backfires?
4: Engine RPM's would drop fast at 1100 when slowing vehicle
5: New right side Cat was glowing red, noticed while installing my new water pump a night
Water pump install went smooth. Noticed an electrical connection covered in oil, that would only be seen with with the water pump off. Cleaned with brake clean, did not take apart, just a surface clean. Same issues. Come out the next morning, truck finally threw some codes, but does NOT stall, no more popping sounds, cat was not glowing and is running smoother!!

Not perfect but 90% better.
The following codes popped up:
1: P0300 Random/multiple cylinder excess emissions detected Excess emissions detected on more than one cylinder
2: P0304 Cylinder 4 misfire detected Injector 4 excess emissions/catalyst damaging level of misfire
3: P0333 Knock sensor 2 circuit high input (bank 2) RH bank signal greater than threshold determined from ECM model above 2200 rev/min
4: P0340 Camshaft position sensor circuit malfunction Open/short circuit to vehicle supply or earth
5: P1175 System too lean (bank 2) Additive injector adaptive fuelling - lean limit exceeded RH bank
Ideas? Criticisms? Just want to tell me off? Anything would help, Thanks!!