Which laptop? Looking for rock-solid, COMPLETELY reliable, and pretty-good battery-life. Don't need high-end CPU.

Skimping on the battery, CPU and graphics is fine.  Having had several laptops from work (and one I purchased) over the years, I've noticed that some are more rugged than others, and some have more problems with heat.  First and foremost, I'm looking for:

• Something physically rugged (though not "military-grade" like Panasonic's tough-book)
• Something that runs cool - this thing will end-up in bed, for long college study-periods
• Something that doesn't have a hardware history of "blue-screens" - some vendor offerings just have a crummy run of hardware (not specific to Dell!)
• Something that has been on the market for about 9-12 months (as-of about next March)

+1 on the 3-year warranty.

Where do you want to compromise?  $500-800 is a budget-price notebook, so you can't have everything. Rock solid and reliable take different forms - all notebooks are made by the same small pool of companies, so there's no difference in reliability between them, if that's what you mean.  You absolutely want a 3-year warranty - about 1/5 to 1/4 of all notebooks will experience a major component failure within three years, and repairs are expensive. Battery life gets better with higher-end systems -- a low-end budget machine such as a $500-800 notebook will have compromised battery life for the sake of lower cost.

Where do you want to compromise?  $500-800 is a budget-price notebook, so you can't have everything.

Rock solid and reliable take different forms - all notebooks are made by the same small pool of companies, so there's no difference in reliability between them, if that's what you mean.  You absolutely want a 3-year warranty - about 1/5 to 1/4 of all notebooks will experience a major component failure within three years, and repairs are expensive.

Battery life gets better with higher-end systems -- a low-end budget machine such as a $500-800 notebook will have compromised battery life for the sake of lower cost.

• Something physically rugged (though not "military-grade" like Panasonic's tough-book)

You're not going to find a new, ruggedized notebook in the $500-800 price range.  If you want that, you'll spend more than $1,000.

• Something that runs cool - this thing will end-up in bed, for long college study-periods

Running ANY notebook on a bed will cause it to overheat.

• Something that doesn't have a hardware history of "blue-screens" - some vendor offerings just have a crummy run of hardware (not specific to Dell!)

This has more to do with Windows than the hardware configuration.

• Something that has been on the market for about 9-12 months (as-of about next March)

Very few notebooks run that long before being replaced.

What you want, is best found in a used Apple Macbook.