if they arnt bolted down try and pick them up from the front corner ( its how you will be picking it up anyway ) and see how much it flexs and creaks
the hinge will need to be robust . it gets opened and closed a lot so wears out
ac plug any good ? it sticks out so is easilly knocked so needs to be durable
the higher the numbers in computing the betterer
2gb ram is better than 1gb . a 2ghz processor is likely to be quicker than a 1.6mhz but look at things like the bus speed too
research the components that are inside the laptop . go for a better motherboard over a bigger hardrive . harddrives are easilly upgraded but a motherboard with the video card combined is going to make upgrading in a few years possibly unviable
"It also has a seat. I don’t use it, but you probably will for the first few years until you build up the muscle."