A windows pc can be just as stable as a mac os-x machine. If you don't add all the junk that home users do then the system can run happily enough without any crashes. It does depend on the setup and the drivers used more often as not but if you have the right ones your system can run fine. My xp (running amd opteron or x2) rigs are quite happy running 40+ hours constant at 100% (well 200% in unix land
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) cpu usage.
As to graphics card arguement - well in 3D creation which is also used in conjunction with 2D work for a lot of people myself included the graphics are important, old graphics struggle with current iterations of high end 3D software.
And windows is just as user friendly for a first time user as os-x. Someone who doesn't know that you can drag and drop a program on os-x would have issues with installing software wouldn't they. Most windows programs autorun an installer. And anyways windows must be doing something right with their marketshare
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.
If you an alternative breakdown of mac versus pc here you go.
Excluding the design of the os as this is as I have said can be configured equally well on either and if you use one long enough you will learn the tricks anyways. Its also a subjective matter and is more personal than one person saying xp is better than os-x or vice versa.
PRO's
vista/xp - more common so more software alternatives available,
cheaper system costs
software is pretty much identical to mac versions (excluding os differences) when comparing the same program, ie photoshop to photoshop.
Current hardware available - meaning better for less money in some cases.
Can add larger range of hardware to machine due to driver based os.
mac os-x - unix based so less issues with software drivers etc.
final cut express etc which are not available on pc - there isn't really anything that competes with this on windows.
Colour accuracy straight out of the box.
CON's
vista/xp - drivers, you need good ones and vista is still new so drivers are a bit lacking in some areas.
virus/adware etc
Supposed software issues when transfering to a mac - I have not seen this and I am in design myself.
Not always good with old fonts.
Colour accuracy needs to be improved on from out of box settings.
No final cut express
If you have used mac os-x more then you will find xp hard to start with
mac os-x
often older hardware (not on all aspects) but especially in terms of graphics.
less range of software due to less market share.
Some hardware is overpriced in relation to what you actually get, macbook (compare to a windows machine of same spec and its about £200 cheaper) and the imac for example.
Limited range of add on cards etc due to enclosed driver design of the os.
If you have used windows more then you will find os-x hard to start with