Hi guys,
I've decided to make a foray into Linux, but I was hoping for some input on partitions:

I have a 160GB hard drive in my laptop right now. I'm using about 60 GB right now with my XP install/personal files all on one partition.
From doing some reading, I believe I want three partitions for 1) Windows install/personal files; 2) Linux install; 3) Linux personal files (separate for when I upgrade (or screw up) my linux and need a new install). My XP partition will be NTFS. I'll be running Fedora 17.

I'm not really worried about the partition sizes - they'll be something like 50%, 20%, 30% respectively - but I am worried about the file system types and being able to access files from both OSes.
My concerns boil down to a few points:
1) I've found utilities for accessing ext2 file systems from Windows, but are there the same for ext3 or ext4?
2) The comparisons between ext2,3,4 that I've seen indicate there are some differences between 2 and 3 in terms of preventing corruption and some speed differences between 3 and 4, but how major are these differences?
3) I've read some bad reports of Linux on an NTFS partition, so I would like to avoid that, but is there any harm in having different file systems on different partitions and accessing them through different OSes?

Thank you for any advice or thoughts!