Mom's Gold Treasure

Hi everyone and Merry Christmas! I am currently in Dallas, TX visiting my folks. My mom has a little treasure of gold coins and tokens I never knew about before now. It's a substantial little hoard. There is only one U.S. token and no U.S. coins, so combine that with my total lack of knowledge of gold, and that's why I'm writing. Sorry it's such a long post, but any comments would be appreciated. All the coins with the exception of the British coin described below are in excellent condition - very shiny, very few marks - but it's a certainty they've been mishandled.

Included:
24 South African gold (1 oz) Krugerands (sp?). (Do these have any numismatic value?), and a South African coin with the date 1967 in legend above a horned antelope on one side; below this device is "2R" On the other,the bust of a man who looks like a Puritan surrounded by a motto in English, "UNITY IS STRENGTH" and what I assume is the Dutch translation.

Also, there are two Mexican gold coins:
(1) The larger is a 50 pesos gold coin. The obverse has an angel, face forward, holding up a torch like Miss L on a Saint Gaudens Double Eagle. The dates 1821 and 1947 are in raised relief on either side of the rock that the angel is standing on. On the left side of the angel device it says "50 PESOS" and on the right, "375 Gr ORO PURO". The reverse shows a centered eagle clutching a branch that seems to be balanced on a rock; the eagle has a snake in its beak. THe legend, ESTADOS UNIDOS MEXICANOS, is on the reverse.

(2) The second Mexican coin is a 20 peso. I don't know which is the obverse on this coin. One side has a circular Aztec calendar not centered, but hanging like a pendant from 12:00 o'clock. Under the calendar is the large legend "VIENTE PESOS", and a smaller legend under that that says "15 GR ORO PURO". The other side has an eagle struggling with a snake in a central device that's so complicated, I can't tell what else it represents. On that side is the date 1959.

Also include is what appears to be a British Imperial coin with Queen Victoria on the obverse. The legend says "VICTORIA DEI GRATIA REGINA FID DEF IND IMP (dots between the words)("Victoria, by the grace of God Queen, defender of the faith (I'm not sure about "IND IMP" - Empress of India?). On the reverse, St George slaying his dragon and the date, 1900. This coin is a little the worse for wear and what looks like somebody scrubbed it on the obverse (the reverse is not scrubbed). Also, there is nothing on the coin (unless it's "IND IMP) to indicate the face value.

Last, there is a medal or token with the bust of opera singer Marian Anderson on the obverse with her name in legend. On the reverse, is a device showing two hands, palms up, holding what is probably a globe against sun rays, and the legend: AMERICAN ARTS COMMEMORATIVE SERIES and the date, 1980.