I started my computer life with a Mac in 1984. A few years later I switched to MS DOS because that's what we were using at work and it was easier to take stuff home and get free programs!
When Win 95 came out and everyone lined up to buy it, my first comment after seeing it at work was, "Wow, windows 95 looks just like a cheap version of Macintosh 84." But I stuck with win.
When I retired last year, I started doing part time work. The company gave me a choice of either a win or mac laptop. I decided to take the Mac since it had been so long - I wanted to see what they were like now.
I liked it so much that a few months later I purchased a new Imac to replace my windows desktop.
I did extensive photo work on both machines as well as a lot of presentations, etc. There is no doubt that there are more programs available for Win. But it doesn't matter at all. For example, let's say there are only 2 nav programs for the Mac and 20 for windows. How many are you going to use - just one.
From a real world standpoint the ONLy place the mac suffers is if you are into a lot of computer gaming. If that is critical, then you want windows since most computer games start life as WIN and may or may not get ported to the Mac sometime later.
Of course with the INTEL macs, you can load windows and run it natively if you wish. If you boot up in Win, your computer IS a windows computer - with all the disadvantages of any win computer - viruses, more crashes, etc. I have Win installed on my Imac and boot up in Win just to run games. I have no other Win programs installed on it. Apple has a program - Bootcamp - that allows you to select whether you want to boot in win or MacOS. You can set it to default to either and, on bootup, overide and switch to the other. There are other non-Apple programs that will allow the machine to hot-switch from one op system to the other. You have to buy/borrow/steal XP or whatever win sys you want, Apple obviously won't supply it. All the major programs are available for the Mac but if you have the Win stuff, you could boot up in Win and run it from there. But I don't see the point. If you want to run win software, get a new win machine.
Almost anything you want to do, the Macs will do it easier. Now that doesn't mean it will seem easier when you are used to Win. I've found that we don't like things that are different, even if they are "easier." Frankly, some things even seemed annoying until I realized it's a better way. Example, if you close your doc(s) in win MS Word, the program also quits. In the Mac, any program stays running until you specifically close it. So you can close all the docs but Word (or whatever) is still running. Why is that good? It means that you can instantly shift from program to program without it having to relaunch. It's really a time saver but the first time it seems annoying - "I closed my doc but Word (or whatever) is still active." Using the dock you can instantly see what programs are active and which are not. You can also instantly switch the same way. It's really handy.
Obviously, you have to start a program for it to open - they don't launch automatically (unless you set them to do so). But once open, they don't close until you tell them - yes, you can TELL it to do so if you wish, the voice recognition capability is very good.
The Mac's Iphoto is an excellent photo program. Google copied a lot of it's features when they developed Picasa - also excellent. But Iphoto is integrated into the mac OS so it's more stable, faster, and easier to work with using other files and programs. Note - Iphoto is NOT an image manipulation program like photoshop although it can do all the basic stuff you would normally do. I never liked photoshop much and used Picture Window for photo work in Windows. I'm trying Apple's Aperture now as a demo and find it to be very good. But frankly I do less serious image manipulation than I used to and am thinking Iphoto does everything I need it to. Overall the Mac integrates a lot of handy stuff into the OS that win machines have to get from add-ons which can cause problems.
I won't get into the issue of style/appearance/elegance of the design. Some people like it, some don't. The interface, however is much more elegant than Win and far less problem-prone. As I said, I used PC's/Win for most of my professional life until April of last year. I would not consider switching back.
I know I sound like a Mac ad - no, I'm not affiliated...
If you want more info/opinion, don't hesitate to ask!