Here's what I ultimately plan on doing:

1. Boot disc to a set of options asking to run diagnostic tools or install XP
2. Before installing XP, it will load WinPE and execute a batch file that asks for a username, password, cdkey, timezone, etc.
3. After answering the questions, an answer will get created and saved to the RAM drive.
4. Thereafter, XP Setup will be run from WinPE and the answer file will be used for install. If a second partition is detected on the system with enough space, then XP install will be copied locally before installation.
5. WinXP gets installed. All settings are fine and dandy. Everyone is happy.

If any of that seems impossible, please let me know what. I have little-to-no experience with WinPE, but I'm fairly confident I can handle this project.

If an answer file cannot be put on the RAM drive and used to install WinXP, then how would I go about putting it onto the user's HDD and run that way?

I'm not asking for a complete guide on how to do ALL of that. I mostly just want to know how to run a WinXP install from WinPE and tell it to use a seperate answer file without rebooting (since the answer file will be in a RAM drive). The batch files and scripts I can do myself, though.

If you make one small change it becomes a lot easier.

Always boot PE and then in pe put up one or more hta forms witch asks the questions you needed.

Since you can use vbscript in or from the hta:s you can generate your .bat files and modify the unattended from there.

As a final point you just would execute your newly created bat file from the hta and mission complete

@Dumpy Dooby
Any progress in that direction?
I'm almost in the same situation and like your plan!