I am probably the last person to take advice from here as I conform my world around Microsoft technologies. I have 17 computers in my house, and the only ones I ever have any problems with are the ones I start to add NON Microsoft software to. Yes, it's true, I am a Microsoft whore! There are obvious exceptions like drivers for hardware devices and some big name products like Adobe Acrobat/Photoshop, etc... I do not have problems with viruses/malware or systems crashing except for one of which was originally our family Room computer but has since been hijacked by Tricia. lol This one has iTunes, Logitech web cam software, maybe some d/l viewers, etc.
Also, my customers that seem to have more support issues than the others generally have more d/l'd software on their systems. Things like AIM, Yahoo messenger, UPS software, FedEx software and some store bought items like Act!, peachTree accounting, Quickbooks, etc...
For the most part, the bigger name company's software should be OK and if it isn't, it's usually a short time before they have a patch out. This brings me to my second biggest tip I can give anybody.
UPDATE YOUR SYSTEM SOFTWARE!
If you do not want to be on the latest release (where they focus the most attention), i.e. Windows Vista
, then for Gods sake, stay current on the patches and fixes released from Microsoft on Tuesdays. it's called "Patch Tuesday" and it's when Microsoft releases all the security and system patches to fix bugs, vulnerabilities, etc...
The first thing I do to any system that I'm troubleshooting is to fully patch it. Not only the Microsoft patches but all the software. about 50% of the time, the system starts working and I'm on my way. Another 45%, after they have been fully patched, I'll move onto looking for malware and remove it, unload whatever A/V, anti-malware, etc software and that's it. The remaining 5% is hardware issues. sometimes bad memory, other times, bad hard drives. rarely a processor or motherboard or video card goes out for me but it does happen.
Just my .02