heres my system specs:
Dell Dimension 9200
Intel(R) Core(TM)2 CPU 4300 @1.80GHz
1.79 GHz, 2GB of RAM

I have dell bios 2.5.3

Which OS X is right for me?

How do i boot from flash drive? i dont have a large enough disk

And finally i looked at guide for installing snow lepard what are these
A Working OS X Installation
A DMG or Install DVD of SL 10A432,
A DSDT (From wherever, compiled or decompiled),
A few kexts, we'll get to them later...