A kitchen is used to create ROMs. It's called a kitchen because its the software that allows you to cook up ROMs with customizations like program choices, registry edits, etc etc. They are not the place to start for someone new to flashing.
Which ROM is best is totally a matter of opinion. Hairy question around here.
ROMs, their flashing and tweaking, and etc etc are the subject of the Touch Pro Upgrade forum:
http://forum.ppcgeeks.com/forumdisplay.php?f=68. It's also linked at the top of this Forum.
To flash custom ROMs you have to unlock your phone first:
http://forum.ppcgeeks.com/showthread.php?t=42503
Then follow these steps:
http://forum.ppcgeeks.com/showthread.php?t=43266
Of course you'll have to pick a ROM. Just go to the upgrade forum and look at the different ROM threads for more information on the different ROMs available.
And of course, welcome to ppcgeeks. And don't be afraid to use this forum's search function. Thanks!