Not that OSX isn't a good operating system, because it is. My only issue with apple gear is that you have to do everything apple's way, or you simply don't do it. Even upgrading the memory or changing the HD on an apple system isn't the straightforward job it is with Windows or Linux.
Thats one of my bug-bears too.. I'd love an i-Mac, and there certainly is some sort of status about owning one.. but as already pointed out the price seems so much more when you compare to what you could get from a system running another O/S. I also wish Apple didnt make it so costly to upgrade things that are simple and cheap on a PC.. nor were they so propreitory about what you can and cant do.
Take my ipad for example.. yeah I love it and yep it is a status symbol to have an
i-whatever. But when it comes to purchasing again/replacing, I doubt it would be apple, because (1) it annoys the hell out of me that I cant put on it what I want (ie Flash), and (2) to add parts that would cost peanuts on another system (such as memory) then you no can do and instead have to purchase a new and more up to date model.
Apple is considered good if you are say into graphics/web design, or music editing, but IMHO for the average user a PC would perhaps be best. I know everyone likes to slate Windows, but when it comes to choice of software or even repairs or support then without doubt PC does have the edge. You have to consider that if going apple then certain software wont be available (there will be alternatives), but it means the transfer of existing data/programmes/apps is going to be harder.
As regards to getting them cheaper anywhere, not really Apple fixes its prices - and retailer prices dont tend to be much cheaper (if at all) than buying from Apple direct. You can sometimes pick up cheaper if you are prepared to go for a model that is just about to be replaced by a newer and greater model.
Ive seen OSX installed within virtual boxes, but IMHO its just a geeky thing to play with if you want to try out some high end specific software.
If you are wanting a change of O/s you could always go for linux.
Granted there was no monitor involved in mine.... but I can tell you that without doubt my new system is higher spec, at less than half the cost, of the imac on sale at £1649. Even by the time you add in a nice monitor you could still make some serious savings.
But if you want it all to work out of the box, if you want it to look smart, and you want to be geeky then by all means go Apple because that is what they are good at.