Will buying a new harddrive help?

[nin137]

my parents computer desperately needs a reformat (they messed up uninstalling drivers, etc. etc.) but my dad is staunchly against it. instead he suggests he just buys a hard drive and installs windows on it instead. so if they get a new harddrive and i put the old one in slave while installing windows xp on the new one, will this help their problem?
their problem is that the computer hiccups every 5 seconds and i'm almost positive it's an issue with some old drivers (while installing his new printer my dad just unplugged the old one and ever since then its been messing up). anyhow, the solution he has proposed is that now we buy a cheap small capacity harddrive and just run the OS from it.
if this seems like it would work, does anyone have any good suggestions for a harddrive?
thanks!
one extra question i have is:
they have all their programs on the old harddrive. if i install the OS on the new one, will they be able to access the programs from the old drive? or would i have to install all of the programs on the new harddrive? ex. if they want to run avg antivirus or a video game. basically can i just install an windows xp on the new harddrive and run everything off of the old harddrive.

[trulad]

First I would try running the XP repair. Boot from CDROM and when asked if you want to install XP click yes. Soon XP will discover that it is already installed and ask you if you want to repair the existing installation. I would prepare beforehand by backing up important files in case something goes wrong and deleting out all of the drivers. XP will install most drivers and others can be installed from your disks or downloaded from the manufactures site.
trulad

[EzyStvy]

"IF" you do get a new hard drive, unplug the old drive and make the new one MASTER. And yes, you'll have to re-install any and all programs.

Once done, hook the old drive as slave.