I think this would have to be my pick of best all round free photo editing software. I found it when I went searching for a programme that would allow me to quickly and easily add a speech bubble to a photo but PhotoScape does a whole lot more than that, far too much for me to remember it all here but here's some samples.

I'm not quite ready to get rid of other graphics editors I use yet but this freebie brings me awfully close. My wishlist for this programme to make it complete would be the ability to make areas transparent (eg. the edges round my boxed hibiscus further down) and the ability to include or add the cursor to a screenshot

Give your photos an antique look

    

Combine several photos vertically or horizontally, with or without borders

Crop your photos

Make a box

Add several pics to make one picture collage

Use the colour picker

Here you can see the left (then right) side of you lower screen from where you can make many alterations including adding filters and frames, cropping, reducing red eye, saving and undo.

You can add many objects to your pictures including speech bubbles, sticky notes, wingdings, text, shapes, xmas decoreations, and heaps more

Take screenshots (although this is one of the few weaknesses of this programme - it doesn't allow adding a cursor to your screenshot. I used the symbols dialog to add an arrow.)

And last but far from least is the print choices which I have not used yet. Here you can print multiple pics on a page, set the size and even print thumbnails

There is probably more I've not found or forgotten already but I highly recommend this programme.