A7N8X-D Overclocking. Need help!

Hi everyone! This is my second time posting here. The last time I asked a question here (which was over a year ago), I received very good advice. I'm not very knowledgeable, so if I ask stupid questions or phrase my post in a way that offends you, just bear with me. Also, if you respond, please try not to use syntax or shorthand, and speak to me as a layman (because I am). Thank you very much!

This is the computer I have. I put together everything in this computer myself, except the processor and mobo (which is the hard part). I am very happy with it, but I know I can improve it more. These are the specs:

* A7N8X-D mobo (I think it's the PCB 2.0, but I'm not sure)
* I have not flahsed the BIOS (I'm afraid to). In 3DMark03 it says "ASUS A7N8X2.0 Deluxe ACPI BIOS Rev 1002 Beta 012"
* 2500 Barton (Default in BIOS is 166 Mhz EXTERNAL FREQ. X 11.0 MULTIPLIER. I think that's 1.83 GHz.)
* 512 DDR400 PC3200 RAM (don't know the brand)
* 2 x 512 DDR400 PC3200 RAM Corsair "Value Select" (Total RAM is 1.5 Gigs)
* 40 Gig Maxtor Drive
* Geforce 4200Ti w/ 128 RAM Xtasy (only 4X AGP)
* I have 2 extra fans in my case. I think it has good circulation.
* ENERMAX, CSX305LS, Black Tower Case, w/ Window, 350W P.S.

I am interested in overclocking this computer. These are my current BIOS settings. When I say "(I think...)", I mean I don't know what the setting is at.

CPU EXTERNAL FREQ. [200 MHz]
CPU FREQUENCY MULTIPLE SETTING [USER DEFINED/MENU]
CPU FREQUENCY MULTIPLE [10.0X]
SYSTEM PERFORMANCE [USER DEFINED]
CPU INTERFACE [OPTIMAL]
MEMORY FREQUENCY [100]
RESULTING FREQUENCY 200 MHZ
MEMORY TIMINGS OPTIMAL [OPTIMAL]
SDRAM ACTIVE PRECHARGE DELAY 8
SDRAM RAS TO CAS DELAY 4
SDRAM RAS PRECHARGE DELAY 4
SDRAM CAS LATENCY 2.5T (I think... I could be wrong)
FSB SPREAD SPECTRUM [0.50%]
AGP SPREAD SPECTRUM [DISABLED]
CPU VCORE SETTING [AUTO] (I think...)
CPU VCORE ??? (I think it's 1.65V... not sure. What should I put it to?)
GRAPHICS APERTURE SIZE [512M]
AGP FREQUENCY [AUTO] (I think...)
SYSTEM BIOS CACHEABLE [DISABLE] (I think... what should I put it to?)
VIDEO RAM CACHEABLE [DISABLED] (I think... what should I put it to?)
DDR REFERENCE VOLTAGE ??? (I can't remember. I haven't changed it. What's a good voltage?)
AGP VDDQ VOLTAGE ??? (Same as above)
AGP 8X SUPPORT [ENABLED] (Although I only have a 4x AGP card)
AGP FAST WRITE CAPABILITY [ENABLED] (I think... what should I put it to?)

Right now my computer runs stable with these settings, but I know I can do more. Are there any other settings in other areas of my BIOS (settings that I haven't listed) you think I should change/verify? In your replies, if you could copy-paste my BIOS settings and redo them so they're optimal for my system, that's what I would most appreciate it.

However, I do have a few main points of interest:

1. Do you think it's safe to raise my multiplier to 11.0x?

2. I am most interested in my RAM settings:
MEMORY TIMINGS OPTIMAL [OPTIMAL]
SDRAM ACTIVE PRECHARGE DELAY 8
SDRAM RAS TO CAS DELAY 4
SDRAM RAS PRECHARGE DELAY 4
SDRAM CAS LATENCY 2.5T (I think... I could be wrong)
Those delays seem a bit high to me. Would it be safe for me to change them? For example:
6
2
2
2.5
?

3. Do I need to change my various voltage settings because I'm running my processor and ram at a higher speed? If so, what voltage settings do you suggest? (Again, if it's possible, please just copy-paste my BIOS settings and make the proper tweaks.)

I apologize for the length of this post. Thanks again for all your help!