MY 98 threw a rod, so now I want to get another S10 Blazer if I can find a clean one, what year would be the best I know the 98 had that cheap intake gasket,

 

intake gaskets basically go on all these trucks. maybe buy another 98 that way you have a parts truck, but off hand i really dont know of any specific years where they had more issues then others

 

Probably 02 1/2 up.

Transmission should have all of GMs fixes.
Double din radio.
No Air Injection (I think no EGR as well).
No Precat to go bad.
0411 (or better) PCM.

All I can think of... well... it'd be newer.

 

I have owned a 97 & 98 Blazers 4x4. The 98 has given me far more problems that the 97. But i don't believe it is because of the years. It is because the previous owners didn't take care of maintenance.
So I would suggest any 2nd gen from 96-04. The 95s were a crossover year, where some were OBD I & OBDII systems. In 96 they went with the mass air induction.
I'm looking @ buying another one myself. There are certain things I want. I want cloth seats, I want a hatch back, not the two piece gate. I don't want automatic climate control, I like the 4 wheel discs but that is 98 up.
I have never had EGR troubles. On the 96-01 for $250 you can upgrade the fuel delivery by installing a Delphi MPI which gets you away from the SCPI. That might be why the 02-04s get a little better mileage. Or at least that is what I hear.

 

4X4blazerguy is right on! Previous care & maintenace is the issue,but stay away from the 95's,in my experience! 96-97's have been great for me(parts interchangeability) and from there on they change year to year! You WILL always have the inherent issues with these units that ran the entire production run(95-05)-I am finding too many of these units around lately that they are asking WAY too much for;a nice 02-05 with 100K should not cost you more than dealer price:$4500-if they want to move it and it isn't mint or modified-move on! Last month I found a true #2 2004 condition Blazer,and they wanted 8K! It would not sell in this town and so they sent it to auction:they got $4500!
See what I mean?