Strange start up problems.

Hi all.
Windows 7 64Bit
2 GB RAM
Dual 6700 intel

About two weeks ago I saw a message pop up stating that there was a problem with a USB device.
I missed the details but when I tried to print something and had hassle I assumed that it was my printer at fault.
I spent hours trying to get it to work, uninstalling it, reinstalling, removing drivers, reinstalling.
The best I got was the printer doing as it should do but in spaced out stages.
It would move the print head, pause, grab the paper, pause, print a bit pause, until eventually it printed the document.
I tried system restore and the printer worked fine.
Then I had the same sort of trouble booting the computer.
I would switch on and get my usual black screen with a cursor in the top left then sometimes it would show the Dell BIOS screen and sometimes not, then take an age to get to the info screen telling me what drives I had etc, then it would take an age to get to the windows user screen.
All seems to be fine once I’m in but now the printer has gone back to go slow.
I’ve scanned for malware but as the trouble is before windows 7 boots I can’t see it being that.
I’ve used the windows utility to test the HDD and there are no problems there.
I’ve tested my RAM, it passed.
This morning I turned on the comp and it hung at the BIOS screen so had to reboot.
This time I got a strange graphic type flash then the part where the red, blue and green logo of windows 7 swirls about was at the top and bottom of my screen, large and blurry.
Once at the users screen all was well??
Is my mobo dying?
Cheers.

Hi Boozad.
Thanks for the reply.
I have a dedicated card, NVIDIA GeForce 7900 GS.

Yes I will try the safe mode but the grief mostly appears before any attempt to enter BIOS, safe mode, etc. apart from that last start up logo strangeness.

Cheers.

I have (I hope) attached a file that I copied from the Dell website.
Apparently this is my current set up.
I don't know if this gives you all you need to know.
If you like I can post the Dell test results (see below) as well.
I have also ran a full check via the Dell web site that tests all my hardware, peripherals etc.
All tests passed apart from one USB device which is an old web cam that doesn't have any drivers available for 7.
This has been attached for many months.
I haven't had chance to try the safe mode yet but I will now.
Cheers.

Spec below.
Other stuff happening.
Internet explorer is saying more and more that it has had a problem, though I have heard that there is grief with security regarding IE at the mo, perhaps just coincidence.
Each time I start up it seems to do it differently.
F8 will not happen, goes to a black screen with the cursor flashing top left.
Makes loads of beeps that represents the amount of time I've held F8 down.
I've noticed I don't get a POST beep, thought it may have been dodgy speaker but the beeps from the keyboard discount that.
I unplugged a USB hub and the computer froze, had to do a hard reboot.
It's all working again now but I have little doubt that there will be other ghostly happenings to report
Thanks thus far.

Not for nothing, but have you checked the battery on your motherboard?