In No Particular Order
1. Registry Cleaners [cleans / fixes registry errors]. Why do you need it?: The system registry is one of the core components of Windows; if not maintained, the registry becomes bloated with useless information (usually a result of installing / uninstalling software) and performance degradation, strange error messages, and spontaneous system crashes ensue. Following are links to the 3, I use CC Cleaner Free, Registry- Mechanic and RegCure - not free but worthwhile if your PC has gotten sluggish or is crashing a lot.
2. Spyware Doctor [an Anti Vvirus-Spyware program]. Why do you need it?: Spyware is by far one of the biggest 'nasties' to avoid when surfing the Internet -- yet we all seem to get hit with it one way or another, no matter how hard we try to avoid it. Spyware Doctor provides three-way Spyware protection for your PC through real-time threat blocking, advanced system scanning, and immunization against known browser infections. Not Free
3. Antivirus programs Avast Home Edition or AVG Anti-Virus Free Edition. Either of these free programs will help to protect your PC from becoming infected with malicious software. The definition of "virus" is broad nowadays and can often infer a Trojans, an Internet Worm, and even Spyware. Both are Free
4. Zone Alarm [a freeware firewall program]. Why do you need it?: A firewall helps to block intruders from gaining control of your PC. ZoneAlarm can alert you whenever a suspect program is attempting to communicate with the outside world and is therefore immensely helpful in the prevention of a Spyware or Internet worm attacks.
5. Revo uninstaller [a freeware program uninstaller]. Why do you need it?: Not all software programs are installed in the same manner. For example, some software authors are very sloppy when coding the install procedure and do not include the proper uninstall information; later, the software may not uninstall properly and (more often than not) leaves leftover "gunk" in the registry, clogging up the system. This uninstaller logs the software installations and is able to reverse all changes made to the system, including the registry.
6. Acronis True Image [a backup program for your Operating System]. Why do you need it?: Acronis True Image goes beyond simple backup programs by archiving each and every byte of your hard drive (and not just the files). If your hard drive goes corrupt or your PC is hit with a virus or Spyware infection, a disk image restoration using True Image is a way to get back into your system with the least amount of down-time (not including a catastrophic hardware failure, of course).
I have it set up to back up my entire hard drive once a week - My Documents folder every 2 days and AOL and Friars email every 2 days.
7. e-Mail: My choice for email is Thunderbird brought to you by Mozilla the same nice people that make the Firefox browser. Both are free. You can even use it to access a gmail account.