Minor Windows Thing

When I go into My Computer I see 4 Removeable Disk drives that shouldn't be there.
I think they are reffering to my 4 USB 2.0 ports in the back of my PC. I have 4 in the back, 2 in the front, and one on this -as I call it- 'super compatability block thing' which has a 3.5 inch disk drive, some memmory card and microdrive readers, and one USB 2.0 port.
My keyboard and mouse are taking up to USB ports in the back, but nothing else is in and of my USB ports. So why does it say there are removeable disks in them? That 'Safely Remove Hardware' tray icon is also there, ready to remove them. I can remove them temporarily if I do remove them from the tray icon, although they just come back when I boot up my PC.
I would also like to point out that it's not a virus because I've had this problem since I bought this PC. Any solutions?
Oh, and I'm using Windows XP Home SP2 (Don't do it ENAY)

The 3.5 inch disk drive is a removeable disc. If there is any memory cards in the memory card reader, so are they

Oh? But... How come there is the tray icon? How can I get rid of em?

That would be it. My cardreaders show up as removable drives aswell, even though there is no media in them. You can hide them with TweakUI if you really want.

Alright. Yeah, there are 4 card readers, that makes sense. Oh and would somebody mind telling me exactly what these readers are for? One little slot says MS above it, the little slot below says SD/MMC (which I figured out I can put my camera cards into),another bigger slot off to the side says CF/Microdrive (iPod's got microdrives right?), and the last big slot says SM.

I far as I can tell, they are all for things that are now pacakaged to plug directly into a usb. (At least thats the way it seems for mine)

The little MS slot is probably for Sony MemorySticks.

CF/Microdrive= Compact Flash. There have been a few Hard Drives made that are CF compatible, these are MicroDrives. My Muvo2 has one :-)

SM=SmartMedia. I think :) Theyre all kinds of storage media.