Startup Screen: No shortcuts; no tray showing

After re-installing MP3 Rocket and re-booting Toshiba Laptop, all shortcuts on the desktop and items in the tray have disappeared. I can open programs by using Task Mgr. but...how can I get my desktop to show the icons once again?
"Start" button is missing, as well. It is a totally blank screen, except for the startup background.

 

Sorry!! I'm running XP Home with Service Pack 3.

I have rebooted into Safe Mode and then simply rebooted again (per a friend's advice) to no avail. Now I'll try to boot into 'Windows Safe Mode' and then select 'Last Known Good Configuration' or 'System Restore' . I'll let you know what happens. THANKS!!!

 

Mark: I rebooted into Safe Mode and selected "Last Known Good Configuration" as you suggested. The desktop opened with all icons, start button, clock and tray. Then, after about 15 seconds, all disappeared and I'm left with the Toshiba empty desktop!! Please help!!!!

 

Nothing....just watching to see that all the icons, etc. came up.

 

Trying now.....

 

When I select "safe mode", I am not given a choice....However on the same screen where 'safe mode' appears, there are a number of choices, none of which is 'restore point'.

 

I think I got it now....I have the option for system restore AFTER Safe Mode comes up.... Working on it.....

 

Completed restore process. Laptop re-booted automatically. Now...it is 'cycling'...screen shows choice of Safe mode; safe mode with networking; safe mode with command prompt; last known good configuration; Normal startup. No matter which one I select, the machine boots up to the same screen!!! Now What???