Beermonster,
The first paw picture is longer than it is wide and it looks as if the claws were not retracted. Why is that?
Well spotted - lion tracks are generally longer than they are wide and exception is when they move across muddy ground (see photo below) - they tend to splay their toes out a bit to get better purchase producing a rounder track.
Leopard tracks are round in shape - one of the best ways of telling the difference between smaller lion and big leopard is the shape of the track. Never seen a Tiger track so can't comment there. You can also tell the difference between male and female from the shape of the main pad. It is "squared off" on the sides its a female if its "rounded" then its a male.
The prints in the photo are in quite deep fine dust so the front toes are showing the fur "peaks" that sheath the claws (rather than the claws themselves) - there is also a little bit of drag due to the deep dust. Sorry .... bringing your thread off of center!
I know exactly where you are coming from though - I feel slightly naked when out walking with out the rifle. Bumped into lion on quite a few occasions without it and it certainly gets the heart rate up! And yes I admit on one occasion I did get my little pocket knife out!
I'd still suggest a taser or bear banger (or anything that makes a loud "alien to environment" noise - even an air horn) if you can get it. My advice would be to avoid wounding the animal if at all possible although if its on top of you your instincts will take over you will fight with what ever is to hand (knife, stick, stone, steely glare).
I've "stopped" a fair few aggressively approaching/inquisitive (delete as applicable!) buffalo simply by cocking the rifle - the alien metallic noise is enough to sow seeds of doubt in their mind.
Generally speaking big cats are at their most dangerous when feeding, mating, with cubs or when you surprise them. If you can avoid these situations then they will run away when you get too near. I'm no expert though and I've no idea about Tigers - my only point of reference is African cats!