Windows Bestiary
Microsoft Corporation makes MS-Windows 95, 98, and ME artificially report its versioning in a particularly misleading fashion, in order to conceal the substantive truth that it's still an MS-Windows 4.x graphical shell and library set running loosely atop MS-DOS 7.x. Even the MS-DOS "ver" command has been gimmicked to incorrectly report the MS-Windows version rather than the MS-DOS one. The correct DOS version can be queried using the MS-DOS diagnostic utility MSD.EXE.
Please note that the commonly used terms "Win95A", "Win95B", etc. originate in what the user sees upon opening Properties on My Computer, but that information is likewise misleading. Best information is shown by "ver /r" for the MS-Windows version, and "MSD.EXE" for the MS-DOS version.
"My Computer" "ver /r" properties at DOS Product says prompt Description --------- -------- ----------- 4.00.950 4.00.950 Original Win95 release (DOS version 7.00) 4.00.950A 4.00.951 OEM Service Release 1 (very rare) 4.00.950A 4.00.1065 Original Win95 with Service Pack 1 4.00.950B[1] 4.00.1111 OEM Service Release 2 - DOS goes to 7.1 (adds FAT32) 4.00.950B 4.00.1111 OEM Service Release 2.1 (adds USB support) 4.00.950C 4.00.1111 OEM Service Release 2.5 (adds USB support & MSIE 4) 4.10.1053 4.10.1053 OEM Service Release OPK3 4.10.1650 4.10.1650 Windows 98 beta 3 4.10.1998 4.10.1998 Windows 98 4.10.2000 4.10.1998 Windows 98 SP1 4.10.2222A 4.10.2222 Windows 98 Second Edition ("SE") 4.90.3000 4.90.3000 Windows Millennium Edition ("ME")
[1] In some cases, this says "4.00.950.1111", instead.
OSR2 has OEM-level support only, comes only bundled with hardware, and has either of two licences:
Delivery Service Partner: adds tutorial disc, transferable lic, $95-120.
Microsoft Easy Fulfillment: single disc, non-transferable, $55-80. Some OSR2 discs include Plus Pack. Microsoft claims Plus is generally compatible with OSR2. FYI, the only parts of Plus not already in OSR2 or free for public ftp are Themes and System Agent.
Your copy may very well differ slightly from the above table, since Microsoft released dozens of variations, depending in part on whether the copy was retail or OEM, and whether it was a full version or an upgrade.