Looks like something happened to one of your drivers.
Your easiest solution may be to perform a repair install versus tracking down the bad driver.
How to Perform a Windows XP Repair Install
I would also try to reseat your ram and test it with memtest just in case.
Bug Check 0xD1: DRIVER_IRQL_NOT_LESS_OR_EQUAL
The DRIVER_IRQL_NOT_LESS_OR_EQUAL bug check has a value of 0x000000D1. This indicates that a kernel-mode driver attempted to access pageable memory at a process IRQL that was too high.
The following parameters are displayed on the blue screen.
1 Memory referenced
2 IRQL at time of reference
3 0: Read
4 Address that referenced memory
A driver tried to access an address that is pageable (or that is completely invalid) while the IRQL was too high.
This bug check is usually caused by drivers that have used improper addresses.
Windows Driver Kit: Driver Development Tools
Bug Check 0x2: DEVICE_QUEUE_NOT_BUSY
The DEVICE_QUEUE_NOT_BUSY bug check has a value of 0x00000002.
This bug check appears very infrequently.