There are a few options:
1. Obtain a version of Linux that resides on the DOS/Windows partition & file system. Can't remember the name of one but
www.linux.org will have links somewhere.
This will allow you to play around with Linux without interfering much with your Windows installation.
2. Install one of the more user friendly Linuxs (Linii?) into its own partition eg Mandrake, Redhat, Corel.
You will need to repartition your hard disk to to this. Partition Magic can do it without losing your data. Like any software it can still muck things up so make sure you back up your data!!!!
Linux Mandrake 7.2 has DiskDrake which can also do this easily. Not sure what tools Redhat have. Corel can also do this but the interface is awkward & difficult to use.
There are also free DOS based tools that can do the same eg Ranish Partition Manager. Ranish was a real lifesaver for me recently. Even Partition Magic refused to work - and it caused the problem!
Install Linux AFTER Windows. Unlike Windows, Linux has reasonable boot loaders that allow you to choose which OS to boot into.
To remove Linux remove the partitions & it's gone. To restore the DOS/Windows boot afterwards:
1. Boot to DOS from a floppy with a copy of DOS's 'Fdisk' on it.
If you don't have a bootable floppy, Win98 has a function to create an emergency boot disk that is very useful. Alternatively format a floppy with the '/s' switch to copy the system files & make the floppy bootable ie in a DOS window type
'format a: /s'.
Afterwards copy 'fdisk' to the floppy.
2. Boot from the floppy & type 'fdisk /mbr'. This will restore the Master Boot Record to point to Windows, allowing Windows to boot. Microsoggy in its inestimable wisdom chose not to document this switch...
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I've been toying with dual booting Linux/Win98 on my laptop for a month or three. So far I've tried Corel & Mandrake 7.2, all obtained from Linux magazine cover disks. Disks of various distributions can also be obtained from
http://www.cheap-linux.co.uk .
In each case I had no trouble getting to a command line Linux environment but neither could get a windowing environment 'out of the box'. Managed to do so with some manual tweaking with Corel, but so far no luck with Mandrake.
Mandrake has a much better installation routine though.
First thing to do is get copies of the various 'HOWTO' documents.
www.linux.org www.linuxdoc.org www.linuxnewbie.org all have lots of information & useful links.
Hope this helps.