Usb drive not recognized

hey everyone out there, I have a problem where my usb port is not recognizing my usb plug and play drive, below are a brief history of what I am experiencing:

-have a dell Inspirion
-plugged usb (Sandisk 2 gig) into port, light blinks but will not autoplay, and will not show up on my computer
-currently have a usb mouse plugged into another port and it works, have tried it with all the other usb ports, it works also
-plugged an external hard drive into the usb port, it gets recognized, but no auto "removable disk" icon/prompt
-when i go into computer management and disk management, I don't see any usb ports nor my hard drives but my hard drives exist and work in "my computer"
-recently had a virus/malware issue
-remedied it with malaware and Antivar

Any clues or hints as to what the problem may be and how I can fix my usb port issues??

My hunch right now is that it is a hidden virus or that I may have erased a file/driver for the usb drives during virus removal? I've ran the antivirus again and nothing comes up. My disk defragmentor has also no longer works....I get a prompt that states "Disk defragmenter could not not start."

Thank you to everyone one in advance

Windows XP