I've found Vista's reliability to be heavily hardware-dependent.
Put another way, I've found it's hardware support to be severely lacking. On some configurations, it will work exactly as designed - slowly, with all kinds of nonintuitive interface choices and a number of "helpful" annoyances, and on others, it will do all that *and* crash regularly, kill perfectly good programs, and corrupt HDD contents. On machines (even "certified vista-compatible" machines) where it's not going to work, it's perfectly capable of destroying your data and it nukes itself into inoperability.
If it's going to work, though, it tends to work as reliably as version 1.0 of any brand-new Microsoft OS ever has, and you're just stuck with it squandering massive resources and with program interfaces designed by drunken rhesus monkeys.
Put another way, I've found it's hardware support to be severely lacking. On some configurations, it will work exactly as designed - slowly, with all kinds of nonintuitive interface choices and a number of "helpful" annoyances, and on others, it will do all that *and* crash regularly, kill perfectly good programs, and corrupt HDD contents. On machines (even "certified vista-compatible" machines) where it's not going to work, it's perfectly capable of destroying your data and it nukes itself into inoperability.
If it's going to work, though, it tends to work as reliably as version 1.0 of any brand-new Microsoft OS ever has, and you're just stuck with it squandering massive resources and with program interfaces designed by drunken rhesus monkeys.