3 random pop-ups related to nothing in general about spyware and viruses

[Smalls]

This is a recent problem that i have run into. When I start my computer the 'explorer.exe' gets turned off or shut down or something, it took me a while to figure out how to turn it back on. But I have to manually restart it every time I start my pc. This is very annoying if you can imagine.

This same problem happens at random every once in a while but it used to start back up after a few second.

please if anyone knows how to fix this problem
please tell me
thanx in adv.

[Smalls]

about every 5-10 minutes there is a pop-up window with 1 of 3 different things.

1 wanting to install an anti-virus scanner

another saying I've got some kind of Trojan at 'C:\Windows\Wml.exe' although I've looked and this file doesn't exist

and 1 more saying I've got a 'Trojandownloader.xs' and that i need a product called ' PC-Antispyware ' to remove them

since these have started showing up i have restored my pc to 'factory default', which restores the pc to what was on it when i got it wiping it clean or so i thought, 3 times already trying to stop these.

Norton says there is nothing wrong

I can't figure out how to stop this

[Smalls]

I am the owner and sole user of my pc, i can do almost anything but i can't do somethings like delete files that were put on it by me but it says that i need administrative rights to perform the action

how can i fix this?