Glad to be of help...
There is a chip named crystal? Nope, not be a b*tch here but still.... :P
If you know someone that can solder and can solder real good get Xecuter 2.6Lite or similar. Some of the best chips ever made.
If you are wanting to install it yourself but are not very familiar with soldering the Xenium SP.I.C.E is very good. Solderless on all versions of the xbox.
Once you have installed the chip you must install a bios onto the chip. I would recommend EvoX M8 Plus 1.6 if using a 1.6 xbox, if you are having a 1.0-1.5 I would say X2 5035 or X24983.
That bios will allow you to run backuped games, emulators, use a different dashboard and use all homemade programs for the xbox.
So when the chip is installed, has the bios on itself it is time to install a dashboard. I usually recommends SlaYers autoinstaller Deluxe 2.6 and will do this now too..
Get hold of that one, burn it onto a DVD and then simply pop it in and restart the xbox. Use the menusystem on the disc (you will see it) and make a format with reinstall standard HDD. It will set you up with a few emus, Xbox Media Center, a sh*tload of other apps and some other things.
Installing ROMS is another thing. When using the retail HDD there can be problems installing plenty of roms on the HDD as it will fill up pretty fast when FTP'ing N64 roms...
But if the HDD is upgraded you open a FTP transfer, go into the folder with the emu, looks for a folder named "roms" or something, FTP the roms there. Restart xbox, start emu and wham play away...
If using stock HDD you must edit the emulators .ini file so that it reads from "A:" (on most emu's this means D: but is named A: for some reason). Then burn your roms on a DVD and put it in the xbox, launch the emu and play...
That should give you some info...