eTerm is a VT102 emulation. You can tailor Putty using it's settings menu so that some of it's behaviour is closer to VT102.
When people talk about terminal emulation, what is being emulated is primarily 1) a set of control-code sequences that are sent by the terminal when you press keys, 2) control-code sequences that are sent to the terminal to move the cursor, change colours etc 3) a set of capabilities (e.g. double-width characters, pass-throughy printing) and behaviours (e.g. auto-wrap at line-end) and 4) a set of characteristics (e.g. fixed 24 lines of 80 or 132 characters).
The whole notion of emulating a VT102 is rather messy. A VT102 keyboard was radically different from a typical 105-key PC keyboard. A VT102 was monochrome. A VT102 could emulate a VT52 (few VT102 emulators do?) A VT102 had lots of settings that could be altered using the terminal setup menu - many of these settings could not be controlled by the host computer.
Why do you want to emulate a VT102 rather than an Xterm?
What specific features of eTerm do you wish to find in Putty?