There are all kinds of doodads available for Firefox, which is what I use. But I could never find a "back button" that would back up 2 pages with one click. They either backed up one page with a left click, or you had to right click to get a menu to choose where you wanted to go back to. In that case if you only wanted to go back 2 pages you still had to click twice. Either left click twice, or right click and select. 2 clicks.
To soothe my nerves I made a Bookmarklet called Double Back and put it on my personal bookmarks toolbar. You left click it. If there isn't enough history to go back 2 pages it only tries to go back 1, to avoid clicking it for nothing. Otherwise it goes back 2.
Since it's a javascript thingy it won't function if NoScript is blocking, but since you probably allowed the current page in NoScript, it should work the vast majority of the time.
Just make a bookmark on your bookmarks toolbar. I named it Double Back but it's up to you what you want to call it. Past this line into the Location:
javascript
:N=history.length;if(N==2){history.go(-1)}else{history.go(-2)}
That's it. Of course you must have JavaScript enabled for your Firefox or nothing happens. It should work on other browsers also but I have only verified the behavior on Firefox. If the page it returns to seems to be "off by 1" all the time, chances are the way the browser calculates it's history is different. Just play with the numbers and you may be able to tune it in.