Like you I have been searching for help on the 26 inch Vizio picture settings. I will tell you what I have adjusted mine to. This is for my Standard TV (SD TV) usage.
First I have my backlight at 60. A low setting will save on the wear of the LCD TV any may cause it to last longer than it otherwise would.
Regarding the contrast I have found using my THX DVD that when setting the contrast above 54 that the whitest of the 8 white boxes bleach out too much and that going back down to 53 and then 52 they all start to appear in their various shades of white. For me the best setting is at 50 or 49.
Now about the Brightness or Black Level I used my DVD Essentials disk and set it at 53. That is for viewing DVDs. When watching Standard TV I set this on 54 because with this tv 52 and 53 is too dark. Now, the free HDTV channels will be a little washed out at this level but you can set it to 51 or 52 to view them then set it back to 54 or 55 when using Standard TV channels. Also I find using the "MODE/Standard or Movie" function on the remote can look good on the free HDTV channels.
I set my color to 43 or you can use 42. If this is too low for you then try a number or two higher but I wouldn't go over 50 because you will loose too much color detail due to over saturation. Using a calibration color picture, I found that the best tint for this TV is right at 0 but this only looks best if the color temp is set at the best levels you can achieve. Setting the tint at 1 or 2 toward the right might give a little more yellow to the skin tones and if you set it 1 or 2 to the left the greens (in grass or trees) look better but that is why I suggest just leaving it in the middle.
I have my Sharpness at 3 because on Standard TV channels I noticed on channel Four that setting sharpness to the number 4 or higher caused a halo around the edges of people's faces and around other forms as well. Setting to the number 3 made those halo lines less apparent.
I have read a lot on Color Temperature and they always say have a neutral gray with very slight red tones. I have adjusted my Color Temp to the numbers as follows: R 127 G 120 or (119) and B 114 or (115). You can see what this does for you. I hope I have given you some help.
On the Advanced Settings I have left them all off. You may try using the color enhancement just to see how you like it and the CTI. Dynamic contrast on my tv causes too much detail loss in the dark areas of the picture.
Remember even the same brands of televisions can be a little different so maybe by starting with what I use maybe that will give you sort of a base to work with. God bless.