FSX without SP2 !

Do a clean install, load SP1 and SP2, then all Windows updates and the machine will run smoother and faster that before.
Then load FSX, I held out until the last moment for SP2 and now all is fine.

First of all, Microsoft is a company not an OS.
Second of all their crappy OS (if that refers to Windows XP) is the most installed, used and sold OS in the world. If you're one of the bigger share holders of Microsoft I'm quite sure you would not find that crappy.

If you are unable to install XP SP2 succesfully on your machine, you have a problem with that machine. Wheter it is a poor installation, or crappy hardware something is wrong. As long as you don't analyse the problem, find it's cause and fix it, you might have all kind of problems that you might like to blame Bill Gates for, but quite frankly it is your problem. (Even if Bill would be at fault somewhere in the process, it is still your problem.)

If you solved that problem, then install FSX and come back here to complain about poor performance thus not only is Microsoft a crappy OS it also can't fly.

ps money/time saving hint, if the problem with SP2 appears to be related to hardware and/or your machine is in need of an upgrade anyway. Your best bet is to buy some new hardware and then you probably need to reinstall your OS anyway.

After you are done reinstalling the machine. Make an image of that disk before you start messing things up. That way if you do run into new problems later on, restoring that image might reduce 2 days worth of work to 2 hours.