Help Understanding E6600 in Vista with SpeedFan

I recently built my new machine with Vista 64-bit.

Here's my full system specs:

Silverstone Sugo SG01 Evo Case
Gigabyte GA-G33M-DS2R mATX Motherboard
Intel Core 2 Duo E6600 (Stepping 6 - Rev B2)
w/Silverstone NT06-Lite Cooler
G.Skill DDR2 800 2x2GB (CAS 5 / 5-5-5-15 @ 1.9v / F2-6400CL5D-4GBPQ)
eVGA GeForce 8800 GTS 640MB Superclocked (640-P2-N825-AR)
Creative X-fi XtremeGamer
WD Raptor 150GB
Seagate Barracuda 320GB
Lite-On SATA DVD-RW
Windows Vista 64-Bit

I am looking to do a little bit of overclocking. I have read quite a few posts regarding temperatures and overclocking but am quite confused now as to what is accurate and safe. Also note that TAT or Core Temp will not run on Vista 64-bit so I am stuck using SpeedFan and Prime95. I ran Prime 95 for several iterations of small FFT to get my temp @ load results. I am assuming Temp 2 = Tcase because it is the only "Temp" value that varies when the CPU is stressed, and Core 0 / Core 1 were within +/- 1C of each other at all times.

I set my memory multiplier to 2.5 (only options on Gigabyte are 2.5 and 3) and eventually got my FSB to 320 so memory is at 800 with 2.5 multiplier (instead of 960 with default 3 multiplier). This also gets my CPU to 2.88GHz. I just care to get my CPU past 2.66GHz (equal to E6700) for now.

Here's my results:

Ambient temp is about 24C.

No O/C:
Idle: Tcase = 31C / Tjunction = 34C
Load: Tcase = 51C / Tjunction = 55C

O/C @ 2.88GHz:
Idle: Tcase = 31C / Tjunction = 35C
Load Tcase = 66C / Tjunction = 69C

What to make of these results? Are these reasonable, accurate, and safe?