In order to complete all of these steps, you will need:
Titanium Backup Pro
A file manager like Astro to install the APKs.
SetCPU can be downloaded here for free: http://forum.xda-developers.com/showthread.php?t=505419
It can also be bought from the Market. The others also need to be purchased or downloaded.
In order to root, follow the instructions here: http://forum.androidcentral.com/veri...-how-root.html
Here is a link for Mac users: http://forum.androidcentral.com/veri...-tutorial.html
ClockworkMod Recovery Installation instructions are here: http://forum.xda-developers.com/showthread.php?t=942021 You can also flash the new recovery with Rom Manager, but for now, I recommend the recovery in the link.
At this point, you should be rooted with CWM Recovery. Now, it's time to install Froyo.
Follow the link here, and you will find Odin files for quickly installing EB01: http://www.droidforums.net/forum/sam...ed-2-11-a.html
NOTE: You will need to wipe when you go from 2.1 to 2.2. Be sure to back up everything before the upgrade.
Now, you will need a rom. I would recommend SuperClean by Adrynalyne: http://forum.xda-developers.com/showthread.php?t=910921 It includes a kernel and there are Voodoo and NonVoodoo versions. This will remove all bloatware, including TouchWiz and Bing. However, the browser will still search with Bing. Then, use the themes sub-forum to find a theme.
You can use ROM Manager-Download-sonofskywalker3 to find all sorts of options. Stock apps, de-Binged browsers, new boot animations, widgets, etc. Anything you didn't want removed can be downloaded there.
If you need to return to stock, you'll need to use Odin. Ask any questions in this thread and I will do my best to answer them. You can also post a thread on XDA(make sure it's in the right section!), or visit the IRC at: webchat.freenode.net channel: #samsung-fascinate
I take no credit for anything here.
NOTE: ROOTING WILL VOID YOUR WARRANTY. I AM NOT RESPONSIBLE FOR ANY DAMAGE DONE TO YOUR PHONE.