Two-part filler has to be mixed and it doesn't rinse off with water, so it's not as user friendly as other fillers. However, it's much tougher and a much better choice for any hole bigger than a nail head, especially outdoors. And it's not just for wood—you can patch metal, fiberglass—even concrete.
Natural or stained woodwork is beautiful, but scratches can really stand out—especially with darker stains. You can make these scratches disappear by touching them up with a stain marker. It's simple to use, and much cheaper than buying whole cans of stain. Start with a lighter color, and if the scratch still shows, go over it with a darker shade. Unless the varnish is in bad shape and needs to be recoated, that's usually all you have to do to make older woodwork look almost new again. If you need to replace whole pieces, learn how to finish and match the stain.