I\'m guessing your windows partition is formatted as NTFS rather than Fat32. Thats a problem in Linux, there are no rock-solid partition resizers that can handle this type of partition yet. I believe there are reliable tools that can handle Fat32, but backups are always recommended.
Under windows I have found PartitionMagic to be excellent, it can detect linuxy types of partitions like ext2, ext3, swap, and reiserfs if I recall correctly. Its the only one I have ever used to resize NTFS ( nt4, win2000 and winxp types, have not tried it with win2003 ) and has never screwed anything up.
If you just want to play with Linux for a while try the Knoppix bootable CD, it will give you a KDE linux desktop with full networking, browser, email, IM client, office applications, image editors, media players, several server applications and a couple of decent games.
If you want to go ahead with RedHat linux, I would recommend using the Fedora Core releases rather than RedHat 9, which is much older than Fedore Core 3, has less hardware support ( due to older 2.4.x kernel ) and 12 months of known security vulnerabilities due to its end-of-support window.