Hi Milly,
Milly, flashing your BIOS will get you nothing. BIOS flashing is used only when there is a problem with a certain BIOS recognizing certain hardware, Harddrive sizes, etc. or other things. A BIOS flash is dangerous at best, and you will see no improvements afterwards.
Let's start from Home again. According to Everest, you are running a 1GHz processor and 384 MB of memory, which gives you the basic requirements for running XP acceptably. It should be running now.
Okay, exactly what is the problem that you are experiencing? WHY do you feel that you need drivers, etc. What is the computer not doing that you need?
This is your chipset driver: Motherboard Chipset VIA VT8363(A)
Go
Here and download the Hyperion 4x1 chipset drivers. Do not use the Pro, just the 4.56 version. Install them.
Remember, if it ain't broke, don't fix it. If XP is running well, doing all that you need, not crashing or blue screening, let it be. If you have specific problems, list them for us.