install SP2 (which, although some may disagree with, I think is a very good idea)
Before you take adven's advice, you might want to check out these two small lists of programs that were 'screwed' by SP2.

Some programs seem to stop working after you install Windows XP Service Pack 2
Programs that may behave differently in Windows XP Service Pack 2

But then again, SP2 fixes lots of important issues
List of fixes included in Windows XP Service Pack 2
Some of these critical issues that are supposedly fixed are as follows:

W32Time reports an incorrect time for how long a computer is on standby
You receive a stop error 0x7E in Pci.sys
The system event log contains many event 61 entries
Palatino and Schoolbook printer fonts are spaced incorrectly after you upgrade to Windows 2000 Service Pack 3
The "NoDesktop" Policy Causes Problems with Displaying the Desktop
Incorrect ToolTip Text Is Displayed
Slow system performance or your computer stops responding when you use Windows

Hmmm, any reason for me to upgrade. . . .