I am new to the 2 stroke and just picked up a 72 dt2 250 and have looked all over for what oil to put in the oil tank and can't get a good answer so would someone please help 

 from near Salisbury, UK.

I usually use whatever semi synthetic my dealer has in stock.

I believe that mixing mineral with fully synthetic should be avoided, but others will confirm this (or not!).

Yamalube 2S seems to work for a lot of people, including myself.  But any two stroke oil rated for use with oil injection should be fine.

I have been using Belray SI7. Its available locally and is a nice high quality oil.

Yeh ,any semi synthetic, Carlube/castrol 2T,/Motul .its all better than the old Duckhams from the 70"s