Joe,
For email, browsing the web, and simple apps like Excel and Word, almost any laptop or netbook will probably work. However, one critical element is portability. How will your wife use it? Only sitting on a desk or in the kitchen? (My laptop is almost always on the kitchen counter.) Moving it around occasionally? Always on the go?
Semi-stationary? 17" screen.
Moving occasionally? 15" screen.
On the go? 13-14" screen and very light.
Regarding your other requirements...
- If she does a LOT of Excel, get the biggest screen you can.
- If she does a lot of email or word processing, get an external keyboard.
- An external mouse is usually important for fixed-base use.
- If she needs mobility and fixed base use, a smaller laptop with an external mouse, keyboard, and monitor gives her flexibility.
I can't comment on a Mac (I don't own one), but with PC laptops, check out each system's expandability. Are there enough ports (typically USB) for mouse, keyboard, etc?
Regarding Mac vs PC, both are good. But each has its pros and cons.
The first issue is price. Unless they has some special deals not showing on their website, a Mac laptop starts at $1,000 and that's with only 2 Gb of memory. Add $100 for another 2Gb and you're up to $1,100.
OTOH, you can get this Lenovo (good brand) for $650 at Best Buy:
Lenovo.
On the issue of operating systems, unless you go with a Mac, I would strongly recommend Win 7. Virtually all new laptops have it as the standard OS. Some vendors may still have some stock with Vista. They might offer an upgrade to Win7 for free, but I would avoid that option. Stick with Win7.
The other issue is consistency with your other systems. Since it looks like you have only PCs in your house, it's probably a good idea to stick with a PC to keep things simple. OTOH, if you like a Mac and believe that it's the way to go, I'd suggest setting up an all-Mac household.
The big issue is integrating the two systems together to share printers and other network resources. Or sharing files over your network. Or connecting to the internet using a WiFi router. It's relatively easy to deal with these issues if you have a single type of computer. It becomes more difficult when you have two types of systems.
One note about Win7 vs OS X... Before Win7, I would have agreed that PCs were more of a hassle than Macs. I.e., Microsoft spent too much time focusing on "nifty" features and forgot what was important to users - speed and ease of use. With Win7, they got religion and focused on the important stuff. Win7 is faster than XP and much easier to use. Is Win7 faster and easier than a OS X? I don't think so. OTOH, I don't think you'd see much difference either.
Regards,
Dan.