If you'll copy down the exact error message, including that "bunch of #s and letters" and post them here, we can start figuring out your problem. That's what they're for; to direct the troubleshooting process. Otherwise, its sorta like saying to the mechanic "My car makes a funny noise".
Take a look
Here for a Win98 Startup Problem troubleshooting list.
Oh, and to start most Compaqs in Safemode, incessantly tap the F8 key as soon as you power on the box. You may hear a beeping, and you may get a "keyboard error" message, but keep tapping untill the boot screen appears (it will). Then select option 3, "Safemode", and hit your "Enter" key.