It sounds to me like you never learned the fine art of beating Windows into shape. See, Windows is pretty good, but it has one huge problem: it doesn't do a good job of cleaning up after itself. It loves to cache everything it can, and leave little junk files lying around after you delete something. After awhile, it starts building up and making things weird. It's nowhere near as bad as it used to be, but you still have to set aside a little extra time to dab at its mouth and wipe the crusties out of the corner of its eyes.
Like I can go months upon months upon months upon years without a single crash or weird bugging issue. I use two programs to make sure it all behaves: CCleaner, and Revo Uninstaller. CCleaner is obvious, but Revo will record every change a program makes to your machine when you install it, and reverse those changes when you decide it's time to get rid of it. Yeah, this is something Windows should do in the first place. Either that, or developers should take the time out to make sure it's done in its place rather than being all lackadaisical about it. But they don't, so you have to rely on something like Revo to get it done in their place.
Also, it's a very good idea to either use another harddrive or set aside a partition for a fixed sized swap file. You'll get tons of varying opinions on the importance of this, but my experiences are that going with a flexible sized swap tends to cause some rare things to act strangely, whereas fixed gives me practically no problems whatsoever.
Windows is more than stable, but it does require a little more proactive involvement in comparison to OSX or Linux. Usually to the tune of a quick sweep once a month.
