When you insert an image using the rich text editor, it gives you the option to "align" the image. However, it does not let you change the "padding" around the image. Certain themes, such as the default theme, do not seem to include any padding for images in their CSS, so if you align an image to the left or right, there will be no space separating the image from the text.
First of all, I dislike using HTML markup, I prefer to use CSS "style" markup to say things like <div style="float:left; padding:5px;"><img src="yaddayadda.jpg"></div>. However, if I use the "HTML view" button in the rich text editor to enter in that code, the rich text view updates to appear the way that I want it to appear, but when I actually save it, the code vanishes, leaving only <div><img src="whatever"></div>. The same thing happens if I say <img style="float:left;padding:5px;" src="whatevs">. The same thing happens if the rich text editor is turned off, with the only difference being that I don't get to see a preview where the page is behaving as it should.
The only way I can get padding around my images seems to be to change my WordPress.com blog to a theme (such as Contempt 1.0) that assigns a default amount of padding to every image, perhaps using the CSS stylesheet. However, what if I wanted to edit the amount of padding for a particular image? There seems to be no way to do this. Besides, I kind of like the default theme, but I can't use it because it doesn't provide any padding for images or let me do images myself.