Hi I'm not trying to promote my home country, but please reconsider this again.
Belarus is beautiful country. People, especially in the rural areas are nice, and friendly. You should not fear anything from them. But you definitely should be concerned about beurocracy
You both will need visa to get through the border.
I assume, that you will fly to Poland, and cross the border by foot, or by car. Right? Then you may expect severe problems with custom officers from Belarus. They will be asking you for various permits, grants, checking on your gear (forget about taking your favourite bushcraft knife), funds, cash, etc. I know what I'm talking about, because my parents in law leave in Moscow, and frequently drive from Moscow to Warsaw. Last time, they waited on Polish - Belarusian border for 3 hours. Why? During one of the stops at rest areas near by Belarusian highway, they cleaned up the ashtray at the car, and frown away the pay toll receipts. Those were necessary to prove that they drove straight from Russian border to Poland.
Don't get me wring. There is nothing bad about the people, or the country. It is just about the system.
I understand that you chaps are looking for real wilderness, with real virgin forests, uninhabited...
Why don't you consider Biesczady Mountains? Have you heard of Transylvania?
Well Biesczady are the part of Carpathian Range. After 1948, when bloody war between Polish troops and Ukrainian underground movement ended with so called "Operation Vistula" (
http://en.wikipedia.org/wiki/Operation_Vistula), the whole Bieszczady was no-man land. Abandoned villages, burned to the ground settlements were reclaimed by nature. Although some of the people returned in 70's, still it is inhabited by relatively low number of people. More you will find here:
http://en.wikipedia.org/wiki/Bieszczady_Mountains.
You can also consider Romanian parts of Carpats. I'm not en expert here, but I can hook you up with people how go there frequently.
In one month I will be in Bieszczady again, and will post some pics.
In the meantime you can goole more on this topic yourself, and also visit my small gallery from January excursion:
http://picasaweb.google.pl/bialoleczanin/BeszczadzkiProlog69012010?feat=directlink
Alternatively, visit albums of my good friend, Doczu, who knows Tatras, Bieszczady and Romanian Carpats like his own palm.
http://picasaweb.google.pl/doczu30
Regards
Puchal