Unable to boot Safemode

Hello I am new and I have a problem with unable to boot Safe mode.
I have tried the F8 with successfully getting the options of Safe Mode, Safe Mode with Network prompt, etc... but when I press the option to start safe mode a bios scroll runs down the screen for a little while then the whole thing resets and goes to regular windows.

To save you time I have already tired the "Safe boot" msconfig option that loads the same way as before but will keep reseting itself over and over again. I am running an Acer Aspire Laptop with windows 7 upgrade Home Premium X64. The laptop originally had windows vista and I upgraded to windows 7 last year. Please help thank you

If your computer will not boot at all then I would suspect hardware problems.

I'm not sure what you mean. I can boot fine to normal windows and activities it's just that I can not get into safe mode. I can get to the selection screen after pressing F8 and when I select any option of safe mode the screen runs a bios scroll then it hangs at

CLASSPNP.SYS.

After that it resets and goes to regular windows.

When I googled, it seems many have had the problem. Many have offred solutions - none of which seemed to work.
But this one got a good response. IF your bios has the option, try this. Go into the Bios and:
1. Disable CPI APIC support
2. Under PCI/PnP settings, set Plug and Play O/S = YES.

And (From me.):-
Open "System" from the Control Panel (icon view).
Open Advanced Systen Settings (over on the left)
Advanced Tab and then "performance"
Data Execution Prevention.
Finally, if not already , Tick the first option - "Turn on DEP for essential Windows programs and services only"
Apply

Okay I don't have the option of the bios change. I tried the advice you gave from the system selections and the control panel and DEP was already ticked. That did not work. Any more solutions?

Only one, I'm afraid.
Open Msconfig from the start box.
"Boot" tab
Tick "Safe Boot" , then "apply" and restart your computer..