Recently I've become concerned about the heating issues my laptop has been having so I did some research.

Turns out Im using a disproportionately large amount of memory even when Im running nothing (Firefox with 2 tabs open and Google Desktop). It says 70% memory usage. If I turn everything off it goes down to 60%.

I've turned off firewall, antivirus software, minimized graphic usage and disabled system sounds on xp, but it still heats up very fast.

I've also updated and ran antivirus, antispyware, trojan detector, defrag and all the standard scans.

How do I prolong the health of my hardware and ensure that my hardware is working well?

Im running a Dell 600m. 512mb ram. 1.6Ghz Pentium M processor with 60gb HD.

Just because your computer is using 60% of its memory doesnt mean its going to die. It just means your computer could use some more memory. You could try upgrading to 1 gb (2-512mb sticks), and you should see a great performance increase. Using the ram isnt a bad thing though, as it makes your programs open and operate faster.

Thanks. But regarding the heating- is that a problem? I'd like to know if there is any way I can at least prevent my laptop from heating up too much. Is heating a problem?

Heating can be an issue if it remains unchecked. What's the temperature of your CPU and / or the system?