While the Treasury may have stopped paying interest on Series E bonds in the 1980s, they are still redeemable by heirs of the registered owner. The Bureau of the Public Debt has a process for redemption of bonds by heirs.
There is a small and growing number of collectors of US War Bonds. There were three different types of bonds 1) large size Defense Bonds, 2) large size War Bonds, and 3) small size War Bonds. Numbers 2 and 3 are pictured in the original post. Here is an example of Number 1

Series E Bonds were issued in denominations of $25.00, $50.00, $100.00, $500.00, $1,000.00, $5,000.00 and $10,000.00. The higher denomionations are scarce.
In addition to Series E Bonds, Series F and Series G Bonds were also issued during WWII. These were also issued as Defense and War Bonds. They were issued in the same denominations as Series E except there was no $50.00 Series F or Series G. Series F have brown Treasury seals and serial numbers. These are blue on Series G. Series F and G had different interest rates and maturity periods than Series E. Series E could only be owned by individuals while Series F and G could be owned by corporations as well as individuals.