Can I use jdk 1.4.0 release candidate ?

I am new to this forum and also to SJCP study.
My friends told me this is the best place for SCJP prepartion (even i can ask very basic questions)
I do not know which jdk to use for testing my small apps for the certification preparation.
Jdk 1.2.2 that came with my R&H book?
or jdk 1.3 or 1.3.1 or 1.3.1_01 or 1.3.1_02
or merlin 1.4 betas or 1.4.0 RC ?
I know that the language part will be the same,
that is Java 2, but for fast compilation and running the programs, which is the best?.
I feel that if I use heavy JDKs it would take time to load all rt.jar and do my tiny app slow.
I come to know that hot spot client jvms are
fast to load.. which one..any info?.
BTW, I use textpad 4.5 for testing my apps, that is ctrl+1 for compile and ctrl+2 for run and with fancy syntax highlighting.
Another stupid question, if i get used to colourful syntax, will it be a problem for my eyes to catch
the code errors in the real exam (i think it is in mono)?
Thanks

I am using jdk 1.3.1, but you should be OK with jdk 1.2.2. or jdk 1.4RC

latha,
your point about the color highlighting is a good one. I use JBuilder IDE, and it formats and colors the text nicely. But you're right, it's harder to just look at plain unformatted source code when you're not used to it. So I would suggest, while you study for the test, to just use plain formatting so you get used to it.
That's just my advice!
Rob