Oil under engine - how much is an issue?

Its not unusual to have oil under an aged engine, rubber degrades, seals go and things do need maintaining.

An angry wife asking you to clean a drive way is reason enough for me to fix a leak but I guess you need to weigh up yourself how much of an issue this is really.
Looking at the photos, I have seen a lot worse. It's not really possible for me to tell where it's coming from though without my own eyes and hands on the engine.

If I was trying to figure where this was coming from, I'd start at the top of the engine and work my way down. Using a flashlight in the dark can reveal easily where fresh oil is a lot easier than in the light. Similarly feeling areas that are obscured will tell you almost immediately if its fresh oil leaking.

main thing is to clean it - clean all the existing oil off the outside, then run it and see from where it turns up.

but to me what you appear to have is either the front main seal (biatch) or oil sump leaking but it's not easy to tell which, ever., unless you clean it first.

it may also be worthwhile nipping up the oil pump bolts - they are known to leak if not done up enough - one of yours is absolutely encrusted in oil, the one in the first photo above the two visible sump bolts.