Seriously Considering a Hard Reset

Ever since I bought my O2 Xda IIi PDA Phone two years ago, I have never done any hard reset. I now seriously consider doing it, seeing that the device gets more and more unresponsive these days. I wonder if there is a standard period of time before hard reset is needed. On desktop and laptop, back when I was still using Windows (be it 98, NT, 2000 or XP), I used to do re-installation like every 3 to 6 months. If I failed to do so, the Operating System would get more and more messy and unresponsive, and would get hung much more frequently (Of course now that I use Linux, I do not have to worry about this kind of thing). So I wonder if the same thing should be applied to the mobile counterpart, not to mention that Windows Mobile 2003SE is less stable than Windows Mobile 5 (and I assume than Windows Mobile 6 too, though I have no experience with it). The problem is that I may not have time to do so during these weekdays. If I am not mistaken, hard reset will delete every software I installed, and I need to re-install them all. It will take time, so I am afraid if I am to do so I have to wait until weekend. It makes me think that I should have probably started looking for a cloning software first (not merely a backup software) so that in the future this kind of thing will not be a hassle.