That is exactly what I suspected. Your partitions were converted into dynamics when you created the 5th partition. Nothing will work with those. The NTFS file system dows not allow more than 3 primaries and one extended partition. But underneath the extended partition you can create 124 logical partitions. You have to do the following:
1. Delete the partition you last created
2. Reconvert the dynamic partitions into primary partitions. The best program to use is Partition Wizard 4.2.2. This is an older version of PW which you can only download from here (pw422): https://skydrive.live.com/?cid=b0a22789320e3247&sc=documents&id=B0A22789320E3247%21215
Note: This is an .iso that you have to burn to a DVD and run the program from the DVD reader. For burning the DVD, you can use ImgBurn: http://www.filehippo.com/download_imgburn/
3. Convert the C partition from primary to logical. That you do also with PW. Highlight the C partition and then the controls are under the Partition tab > Modify.
4. Now you can create an additional logical partition where you can install XP
Note: On your system, Operating Systems can be in logical partitions because you have the primary System partition where all the BCDs go.