My 2 year old Compaq Presario freezes during startup at the Windows 98 logo screen. I tried using "ctrl" key to do step-by-step execution of my sys files. As soon as it hits the line "process windows regitry" or "himem.sys", it freezes. I cannot boot using a floppy also. I have tried multiple system floppies. On some of them it says I/O error and some it says "invalid system disk". Is there any way I can boot?

Kinda sounds like a hardware problem. RAM??

Agreed .. this sounds like a RAM issue. Whenever you get totally random errors that just freeze up with no solution, it's often a bad memory module that's the problem. Replace it with known-working ones and try again. Good luck!

What for model do you have? it can be a double problem, fdd drive bad and a fault on your hdd. The first thing to do is press F10 (by booting) for entering the compaq setup and diagnostics, if this run fine try to run the diagnostics from hdd (if available on your system, I don't know which model you have). if the system give a error by accessing the setup then check the hardware: mem, sysbd. else replace first de floppy drive and look if it works. You can also remove a jumper on the sysbd to clear the cmos (jumper information inside the computer). A clear cmos is a great tool on a compaq computer...