TTL settings for Tor

[misc]

I'm using Tor 0.2.0.22 and it's very slow.

Is there a way to tune TCPIP parameteres in Windows to better work with
Tor? I'm talking most about values in this registry key:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters]

For example, should DefaultTTL be increased, so that packets don't expire
in transit? What TCPWindowSize is better suited for Tor?

My browser connection constantly times out, even though I set timeout to
1200 (as opposed to usual 300). 

Any suggestions?