Yes I would also suggest to move to 8.x (mostly out of support ) or 9.x.x (current support)
No more legacy wM 6.5 installs… 
If it still stuck, try to Kill the server process (PID or java.exe) Before you start clean up the files in the folder
WmRepository4
XAStore
DocumentStore
Make sure you have OS enough memory available to bring up the IS6.5 (with sufficient jvm heap settings) and check the logs as it boots up.
HTH,
RMG
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