I have some questions about old IBM laptops.

Without the exact model number of the laptop and based on the information that it's a Win98 laptop with an internal floppy disk drive, your best bet may be to purchase a PCMCIA Wireless card. If you're lucky, that laptop may have USB ports, but it's likely to be USB 1.1 ie. max 12Mbps, therefore 11Mbps wireless connection max. With a PCMCIA card, you should be able to connect to a 54Mbps wireless access point. However, this all depends on the exact model of the laptop. Regarding the upgrade to WinXP: if permitted, you'll want to set the device boot order in BIOS setup to allow the CD-ROM drive to boot before the harddisk. But, if it's a very old model laptop, there may not be the option to boot from CD-ROM. If this is the case, you'll need to boot from a floppy boot disk and manually start the setup process off the CD. Failing that, and it turns out that the laptop is an antique, the extreme alternative is to format the harddisk to system bootable FAT32 on another computer, copy setup files and then boot up after reinserting the harddisk back in to the laptop - I had to do that with an old tablet PC...

Installing XP is quite direct because XP can support those Thinkpad oldies.Get a XP cd,and you're ready to go by booting form the cd.If you wanna go wireless,I suggest using USB wireless adapter.It is much easier than upgrading your ethernet card.Btw,there's a lot of cheap adapters sold on the net.