Probably you're aware of the free software or web-based programs that's now available to compete with some of the paid programs. I'll be listing those as well as a few others that might help you in your mission toward a frugal but fulfilling life. I will just mention that I've culled from "The Best of Free Software" article in PC Magazine's March 2008 issue.
For the best of the best for all around great software and applications, consider Adobe Reader for opening PDF files as well as online collaboration, Firefox for a secure web browser, Open Office or Google Docs as an alternative office suite to MS Office, Skype for calls and video conferencing, and Audacity for recording or editing. To protect your PC from viruses and malware, you have some great choices including avast!, AVG Free, Avira AntiVir Personal Edition, Hijack This, NanoScan, and Trend Micro House Call. Firewall offerings include Comodo Firewall Pro and ShieldsUp!.
In terms of household management, here are a few worth investigating: Backpack for a To-Do List, Google Calendar, Yahoo! Calendar or 30 Boxes for tracking your schedule, and Remember the Milk for creating your grocery lists.
Moms love their pics so here are some programs to review the next time you want to edit or manage your photos! Paint.NET is as close as you can get to a free Photoshop, thanks to a student project. Picasa is Google's photo manager. Picasa, Picnik and Windows Live Photo Gallery all provide editing features such as red-eye reductions, exposure adjustment, and cropping to name a few.