Hugh, the issue that is a hybrid question is how the scanner renders the grain. You will find a reference to how dye clumps and such are rendered... in short, the grain you see from a normal scanner is not the actual film grain but rather something a bit more clumpy. So there is a real reason why when people compare digital files to film scans, they are not doing the film justice.... most of these films were simply not engineered to be scanned (if they were they'd have no mask, for starters). Having said all that, again, your enlargement factor is quite small so I don't think it'll be an issue. If you flatbed scan and it is an issue then oversample (2x or 3x) at 16 bit per channel, do a quick grain treatment, then downsize and *poof* the grain will be gone. The film image contains waaay more info than you need for your enlargements. if you do a drum scan then the operator should know how to diminish the appearance of the grain via aperture selection. You can help him/her or yourself out by erring on the side of overexposure.

Concerning mixed lighting, I do not agree that digital post processing fixes the issue... at least not entirely. There is a big difference between doing auto white-balance on a raw file (which has r,g, and b info stored separately) and doing the same thing on an image where the colour channels have already been combined and thus their colour renditions are already mixed. This issue is the heart of why raw processing has become de rigueur in the digiworld. Anyway this discussion can be had elsewhere, as noted....

Anyway, my experience is that the fuji pro handles the mixed light like a champ.