What Alan says, although I'd clarify my own views slightly further:
You want to aim to be spending as little time in post production as possible. For two reasons: it frees you up to be doing more worthwhile things(!) and everybody's aim should be to get things as close as possible to perfect in camera, first. Some things such as getting someone's hair right in a portrait takes seconds (depending on the hair!) of adjustment by hand "in real life" but could take half an hour of cloning in post. Have a critical eye and look throughout your frame before pressing the shutter.
Then, when it comes to post, you're touching up a few things here and there. Maybe a spot or two of dust removal but as Alan says, pretty much everything else depends on the image.
I would encourage the use of a range of presets (e.g. setting noise reduction to 10, 20, 30 etc. and separately settings for different sharpening levels and thresholds). These can definitely save time. But, what is essential in these presets (let's not call anything "defaults" here) is that you have a variety to choose from, depending on what the image needs.
I learnt Lightroom by watching a range of videos from the likes of Serge Ramelli etc. Whilst I learnt a few things, I also learnt a lot of what I don't like to do or see: "on every image, you'll see I move Highlights to -100 and Shadows to +100..." this kind of default action is fine if you are either ultra consistent in the types and exact exposure range of every photo you take (almost impossible) OR if you want all of your landscapes, say, to have the same "Serge Ramelli" look. Now that might be fine for him because he clearly makes tons of money from what he does and people buy it... but if he posted his images on here I'd expect them to receive quite a bit of "nice original image but that's overprocessed" comments
Instead, you might have a "recover lost shadow detail" preset which sets Shadows to -75 (I'm using LR examples here rather than Elements but the principle is similar) but you'd also have "recover some shadow detail" which is -50 and "boost shadows a bit" of -25 say. Now, for just changing a single slider, it's almost not worth it except for things you'll be doing a huge amount - I'd still probably rather drag the slider myself than click a preset for shadows or highlights - and certainly contrast. I'll be honest and say I absolutely use the "Auto" button a lot - but simply to see what it sets Exposure to. I then hit Ctrl-Z (undo) and make the changes I want individually - depending on what I think the image needs.
Before I do anything, I ensure I've imported the image using the embedded camera profile (rather than the Adobe standard) as I prefer the warmth my camera RAW file has by default. It ends up being a touch redundant if I've then shot a grey card or manually pick the white balance, but it's in my workflow.
The key things I think about: white balance (shoot a grey card shot if you want it bang on!), exposure, shadows & highlights, contrast, white & black point (I sometimes use Alt when dragging the white point but even that I'm doing less and less now), saturation & vibrancy (more often than not to reduce the former and I don't often touch the latter), clarity (may be a LR only adjustment but it's a helpful one if not overdone), tone curve (if I want to get a particular look but small changes have a massive impact), sharpening & noise reduction. Many of these settings I will decide "I don't want anything here" and in a number of low ISO cases, I'll apply no sharpening or NR.
Finally - and I do this last because it slows down Lightroom - I apply lens correction (distortion correction, vignette removal and aberration correction). It's a great feature of LR which ACR may well have as well but I apply it last because otherwise it makes certain parts of LR5 go slow (cloning and spot healing for example).
Most images, except portraits (which I'll often take into Photoshop for touchup) I probably spend less than a minute on. Occasionally macro shots might take a bit longer if I want to bring out selective detail.
Right - I'm off to take a sunrise photo so I'd better get going otherwise I'll miss it!
but it was worth a try 