The 1928 $20 is the most valuable of them all. If thats the one with the stain, I can't see it that well.
The 1934 $20 lists for $25 in VF condition, 35 in EF, but I doubt its EF.
The 1928, I can't tell what series it is. Is it plain, A, or B next to the date?
If it's 1928 plain, then it's $50 in VF
If it's 1928 A, then it's $90 in VF
If it's 1928 B, then it's $45 in VF
The 1928 note you have scanned is a "numerical" district note. They made the 1928 series with some numerical and some letter district notes. A=1, B=2, F=6, etc.
The 1928, in my opinion is a very nice note to collect. I am very confident to say the numerical districts are harder to come by and are more valuable than the letter ones. Even with the stain, the note you have scanned would sell for $40+ on
ebay. Pretty sure...
Again, the scans are too small and I can't read the dates on the $5 silver certificates. For the most part, both the 1934 and 1953 $5 silver certificates sell for $8.50 in VG to $10 in fine to $12 in VF and EF condition. I wouldn't buy these for more than $10 since thats what they go for on
ebay. Even at the flea market I can get them for $8 some times.
The Red seal note is $12 in VG, $14 in F, $18-$25 in VF... This is for both 1928 and 1953 series. However, the 1928 D series sell for $25-$95, depending on the condition.
Hope this helps, and the 1928 really isn't a bad looking note. I would be all over that one before I would worry about the others.
Ty