Sometimes when your computer is bogged down by so much, it's easier to just start over and wipe everything (after backing up anything, of course).

I do it when I notice that I really, really need the speed back. Sometimes the computer just kinda... slows into a crawl under normal usage. It's a way to get things back to normalcy, though it also takes more effort than usual.

Yeah, I usually wind up doing that once a year or so. Back up all my data, re-install OS, and then re-install programs only as I need them.

I've thought about doing that, but seeing as the main machine that I use is shared by my dad and I, (two separate users), and noting how many files he has of his own on the C: drive, that probably wouldn't be on the top ten list of the smartest ideas I've ever had.

I've had my computer for 3 years or so and the speed drop has been negative... so it's actually gotten faster. Whenever I noticed a drop in speed, I investigate the cause of that drop and solve it right then and there. I have yet to find an issue that I haven't been able to solve on the spot.

Long story short, no. I don't wipe and reinstall. Also, I don't have a way to backup my programs (unfortunately).

I do it once a year. But normally I will just look for programs to remove that I don't use anymore or will never use, and delete some files that are useless as well. Then I turn it off and turn it back on and it is better and faster than before.
(I know it sounds stupid and stuff, but that's just how I do it.)

I don't wipe my drives clean, but I do reinstall my operating system, mostly do I have one partition for my downloads and documents and another partition for the operating system and games.

Basically, I use partitions as I have no backup drives.

I avoid that as much as I possibly can and solve most of my problems with system restore, norton ghost, or google and forums. I haven't reinstalled in 2 1/2 years and that's only because I put Windows 7 on as soon as I got my paws on it!