Yes you can, but they won't fit on most road or CX frames because the dropout spacing is different. Wheels will build fine, no problems, but getting them on the right bike might be a different story.
the point is I have an old DH rig that has a crack in the frame put is still good enough to commute with I just want to get a but load of speed out of it I will be changing to gears also after I figure out what size I will need
this is my Specialized Crosstrail with Shimano Deore MTB hubs and Mavic 700c rims
this frame has 135mm OLD rear dropout spacing and 100mm OLD front fork spacing (I am using a Kona Project II hybrid fork rather than the original Suntour suspension fork)
the point is I have an old DH rig that has a crack in the frame put is still good enough to commute with I just want to get a but load of speed out of it I will be changing to gears also after I figure out what size I will need
I put Messenger slicks on a burly bike years ago and it tore around like a road bike almost (geometry aside obviously). I believe they were Panaracer but there are lots of 26" road tires that would be much easier and safer than building up your proposed wheel and bending dropouts...
I believe the tires I used are Messenger T Serv kevlar 1.25x26 and let me tell you they grrrrrip and rrrrip.
To actually answer the actual question: Yes if the number of spoke holes in the hub and rim are the same. You can build that wheel. It may fit in some or even most MTB frames. The hub may not fit in some road bikes, although, if its a steel frame and non disk brake you may be able to squeeze it in, but not recommended.
I'll use this space to vent a little. And if you have a specialized sirrus cross bike like me, it will not fit as the rear end is 120mm spacing and only the original specialized hub will fit. The bike is hanging up for want of a rear wheel.
Yes we swayed a little OT however the wheel compatibility is not what gives us the speed so I thought it was relevant.
The OP's needs:
the point is I have an old DH rig that has a crack in the frame put is still good enough to commute with I just want to get a but load of speed out of it I will be changing to gears also after I figure out what size I will need