Win98 reinstall hangs on start up; Troubleshooter not available

I just reinstalled Win98 because my computer’s been crashing frequently. (It
was originally a Win95 machine that I upgraded to Win98SE a few years ago. I
suspect the problem was spyware/virus. Spybot Search & Destroy found DSO
Exploit. I tried to clean it, but it kept reappearing when I reran SS&D.
McAfee Stinger crashed when it got to Explorer.exe. But TrendMicro’s
HouseCall didn’t find anything.)

When I start up, the computer gets to “Windows 98 Setup: Windows is now
setting up the following items: Control Panel�; it draws a green line across
the blue background; then it hangs. Never gets to “Programs on the Start
menu,� etc. If I respond right away, Ctrl+Alt+Del will restart it, otherwise
I have to hit the computer’s physical reset button.

I’ve tried starting the machine in Safe Mode, pulling up Windows 98 Startup
and Shutdown Troubleshooter in Windows Help, and selecting “My computer stops
responding when I try to start Windows 98.� (BTW, the text of the 4 choices
has a gray, textured background.) When I click on Next, the right-hand box
goes blank and nothing happens, no hang, no crash. (The rest of the Help
window is still there and operational.)

How do I get it to start up again?