Some applications let you turn off the notification icons in the system tray. If and you can hide notifications and icons but I see you have already looked at that. This isn't a 7 issue, it is more of an application issue, try posting in the application section and make a list of the programs running in the tray.
1. run regedit.exe 2. exit explorer via taskmanger or ctrl+shift+right click on start menu. 3. navigate to and delete IconStreams and PastIconsStream keys in registry. 4. close regedit, use ctrl+alt+del to reboot w/o explorer being restarted. After reboot, system will clear all past items and rebuilt from there on. Hope this works for you.