I used cwm to restore back to before I installed the ROM and kernel. Then, I redownloaded the DJ05 ROM, everything working fine, then I was stupid and heard good things about stupid fast, so I downloaded 1.54, now my phone will not go past the "SAMSUNG" lettering
Few things... while ROM Manager/ClockworkMOD can flash kernels, it doesn't back them up. When you do a backup, all it backs up is the rom, cache and data. So, it sounds like what you did was flash JT's DJ05 ROM and his Voodoo kernel. Restoring a backup shouldn't have caused much problems because it was just restoring your ROM. So at that point, it sounds like you had the stock ROM with JT's Voodoo kernel. But, then you flashed one of the StupidFast non-Voodoo kernels. Voodoo needs to be completely disabled before flashing any other kernel.
So, first you need to get rid of Voodoo.
Here's a detailed thread with instructions:
[HOWTO] Completely Remove Voodoo Lagfix - xda-developers
Or, this supposedly *completely* restores your phone to it's factory fresh state - ROM, Kernel, Recovery, Modem, everything. It will supposedly remove Voodoo, but the OP states you should try to remove it by other means first. Not sure why that is.
[ODIN] Full DI01 ODIN Package - xda-developers
Once you're back to stock, re-root if need be, and then just steer clear of Voodoo. It's fine if you know the limitations, but like I said, for most, it's more trouble than it's worth.
If you want to upgrade to DJ05, you'll have to use JT's kernel or one of the StupidFast ones. Personally, I've never seen any performance increase, and I've seen significantly shorter battery life on every StupidFast kernel I've tried.
I'm currently using the stock DJ05 ROM with JT's non-voodoo kernel, and everything is running perfectly. It's been 24 hours since I took the phone off the charger, and I still have 75% battery... can't ask for much better than that.