The PC vs Mac debate has raged on forever it seems, each has their respective strenghts and weaknesses.
Compatability issues only come down to being a prolem if you absolutly require trading proprietory files for programs that only run on a PC.
We use jpeg, gif, text, zips, RTF, Word, Excel and so on, we have OfficeMac, Appleworks, and all sorts of programs that run just about everything. We email PC users, view the same webpages and everything else, trade files, in fact a lot better than PC users because Apple takes great pains to make sure it all works well, instead of things being kludged together like Windows does.
We also have Virtual PC, which will run some low intensity PC apps in a "Windows enviroment" if that's absolutely necessary.
If a Mac apeals to you get one, they are really great machines. I have been using them for over 20 years and only caught one virus 17 years ago. Now on the other hand Windows PC's seems to have exploits every week or so, a hundred thousand pieces of malware so far trying to infect your PC and more being created everyday.
In fact I read a article that in Poland over 800 PC's out of 1000 are totally infeted with spyware!
Some who have used both platforms say the Mac works for you and with the Windows PC you wind up working for it.
In the corporate world and buisness in general, PC's dominate, because they are cheap and "just do the job", on the other hand Mac's are used more in the creative fields because they come standard with more high speed interfaces to external drives and devices. Video, images and music files are very large in their raw formats. Also the OS and software has to work well because buisnesses like newspapers depend upon their machines working, if a newspaper print deadline is missed, hundreds of thousands, if not millions of dollars in advertising revenue could be lost.
So when you see a price for a Mac and then a PC, you have to compare feature to feature and no site I know does it better than this one.
http://www.systemshootouts.org/shootouts/desktop/2006/0114_dt1300.html
However what makes a Mac really shine is the continous innovations to Mac OS X, the operating system, it's always light years ahead of Windows in it's ease of use, power and security.
As you research the history of computers, you'll find out Apple was first with the mass marketed graphical user interface which interacts with the user, Windows is a copy of the Mac OS, so basically they are both the same, just a tad different. But unfortunatly the copy is not nearly as good as the original.
Apple is the undisputed leader of innovation in the computer world, however to maintain that cutting edge, you have to buy a Mac to get Mac OS X. The hardware and software go together for the best in reliability and experience.
On a PC you have the option to slap something together at home and install Windows on it, so it can be cheaper, but less reliable.
So if your new to computers, you should get a Mac, because it will work right and you'll get up to speed with computers without getting disinterested.
On the other hand if you get a Windows PC, you'll pretty much have to take a crack course in computer science to keep it from becoming owned by some hacker and spewing out tons of spyware daily.
After using the Mac, you might decide your not really interested in computers like a car mechanic is interested in cars, wanting to tinker with them all the time. You might just want to get things done and do other things with your life.
However if you take a serious liking to computers and become more of a "geek", wanting to customize your own machines, build them and the like, then you can get a cheap PC and toy away.
You should really tell us what you plan to do with a computer, how long you intend to keep it and how much is your budget.
Obviously the cheaper Mac's have less power, less features and get old quicker, you can't do as many things as the higher powered machines. Do tell us if you require portability, desktop machines last a heck of a lot longer and are more powerful usually, but they are not portable.
I might not be able to answer you, but others can, also take a look at my machine, you'll need Quicktime installed to view the videos.
http://homepage.mac.com/hogfish/PhotoAlbum2.html
Also read about Apple's switching to Intel processors (which the new Mac Book Pro and iMac now have)
http://appleintelfaq.com/