IMO those rims and tires look fine.
In my research two other black rims would also look very fine on late 90's Tahoe: the American Racing "Trench" (17x8) and my second choice would be the Ion Alloy Style 179. Until I can upgrade, I am living with my flat black painted stock 16" rims.
As for tires, you will have to be the judge as to what will work in your neck of the woods. I needed new tires quick when I bought my '98 Tahoe and these 245/75R16 LT, Total Terrian A/T were on sale. I normally am not a fan of Good Year Wrangler's, but the Good Year Wrangler Territory in 265/70R17 would probably work very well in my area. Might work for you??