And, of course, color capability is handy if you're doing any sort of digital imaging. Resolution is the key, and more is better. They're always included with a system, but Microsoft, Logitech and others offer better ones, from both style and ergonomic standpoints. Once you've used a mouse with a wheel that lets you scroll without clicking on the scroll bar, for example, you're hooked. Check them out.
More resolution is better.
For word-processing, it's either Microsoft Word or Corel WordPerfect. In terms of functionality, only their mothers can tell them apart. Home financial software is either Intuit's Qiuicken or Microsoft Money. Many computer-related retailers are honest, but, as in any field, some are not. Credit card companies will put a disputed amount on hold until the dispute is resolved, which gives you a little more leverage.