Inspiron 9300
Windows XP sp2, Home Edition (all Windows Updates installed)

For about a month now the startup time has changed. It loads normally until I get to the "Windows is starting up" - "Welcome" screen. From the welcome screen it takes about 5 minutes until all activity stops and the computer can be used. Once the wallpaper loads it takes about 15-30 seconds for the taskbar to appear (no icons in system tray/notification area), then desktop icons (all look like generic icons, then slowly by twos and threes they change to their proper program icons), and finally the system tray icons appear next to the clock.

At the same time that startup times have changed I noticed that the power icon is sometimes missing from the system tray. For a few days it would appear or be absent at random, but after about a week it took on this pattern: it's missing from the system tray every other time after shutting down/powering up. Restarting sometimes brings it back; logging off then on always brings it back for that session, as does going into power options and unchecking the "always show icon..." box, hitting apply then rechecking the box.

In the three years that I have had this computer the power icon only ever went missing about 2 or 3 times, and now it is missing on a regular basis for the past month.

Here are steps I took to try to resolve the issue: ran disk cleanup, defragmented, checked my startup and services lists (everything that is there used to be there before, when startup times were normal), ran CCleaner (registry cleaner), ran antivirus and anti-malware scans on the machine and online (nothing found), and ran dell extended diagnostics (all tests passed) - none of them helped.

I noticed that a number of users had similar issues but did not find any instances were the power icon and startup times issues coincided; also, none of the fixes mentioned in other threads worked for me.

Thanks for reading my long post, any thoughts on this are appreciated!