i have win98, today when i turned on the pc it displayed 'invalid system disk' then i decided to reinstall win98, inserted the startup disk but the pc comes to standstill with the message 'verifying ool data' plz help

Make sure that the data lead has not come out of the back of the hard drive or off the the connector that goes to the motherboard

conections with the hdd are intact, but there is a noise from the hdd. does that mean there is something wrong with hdd, if so how can i know?

It's probably dead but you can download a diagnostic from the hard drive manufacturers site to confirm it.

When it said "invalid system disk" ??? could have you had left a disk in the A: drive, ahhahahahhah and You tried to reinstall windows! Win98 how did you do it? did you format the hard drive and then reinstall it or just try and install it over the top of the previous version! and if so did it Freez as it was loading? coz if so thats why you could be recieving those messages, but its always good to check your hardware b4 you check software, so try downloading a small program called PC-Check (fits on a floppy) and place it in the A: drive on boot up, this will do a hardware check on your computer and tell you if its hardware or not.. anyrate good luck. i say if you find its a hardware problem, grab your computer go to the tallest building in your local area and though it off, run down to it and set it alight and dance around it drinking cheap wine

roflmao ive just had a similar problem but all is well now i thought that the hdd was knackered and my heart sank to a new low but now it is still ok im full of the joys of spring (well autumn) ill bear it in mind for next time though will cheap whisky also do the trick?

Sounds like your hard drive has given up. Can you boot at all from A Drive. If so, do a chkdsk on the drive that appears to be duff.