desktop icons and task bar are missing

hello.

Could somebody please help me?? everytime that I turn my pc on, the desktop icons dont appear, not even the task bar, nothing.

I started to have this problem since the last time I downloaded system mechanic, and I was told to remove it and do a system restore in safe mode, which I did, and my pc worked again, but now, after a week I turned it on and this started to happen again, I did system restore again, and nothing.

Any tips or suggestions would be really appreciated, thank you in advance

Win XP, Version 5.1 2600 SP2 Build 2600.
HP Pavilion 05
System Type x86 based PC
System Processor x86 family 6 Model 8 steppin 0 AuthenticAMD~1798

See if anything here helps:

http://h10025.www1.hp.com/ewfrf/wc/d...=en&rule=59557