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I've had very similar problems. While I don't share your opinion of it running okay generally (far from it) I've had lots of trouble with programs toggling from one to the next and, as you say, resuming. It seems like after resuming they'd always run noticeably slower.

LOL i toned down my problems so no one accused me of being a apple-anti-windows- fanboy.
 
your first problem is that it's a laptop. but once resigned to that, then (as some have suggested) swap out the ram for 4gb ($60-70 frys) and tighten up vista. or wipe vista, and install xp.
your desktop xp: adding ram to bring it to 512 or higher would be good, but old ram is pricey (unless you know someone who keeps spare parts).
 
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