3 of 4 added 236 characters in body

C, 230 200 characters

EDIT: Shortened it from 230 to 200 characters.

My first golf attempt. Maybe not a hole-in-one, but it works. Not being allowed to use strlen for this forces it to be fairly verbose in C. Maybe it can be shortened a bit?

int a,b,w,i,l;
int main(int c,char **v){
    for(i=0;(a<256)||(b<256);i++){
        if(!v[1][i])a|=256;
        if(!v[2][i])b|=256;
        if(!(a&256))a++;
        if(!(b&256))b++;
    }
    a&=255;b&=255;
    w=a>b?0:1;
    l=w?b:a;
    printf("%s %i\n",v[w+1],l);
}

Or the uglier version:

int a,b,w,i,l;int main(int c,char **v){for(i=0;(a<256)||(b<256);i++){if(!v[1][i])a|=256;if(!v[2][i])b|=256;if(!(a&256))a++;if(!(b&256))b++;}a&=255;b&=255;w=a>b?0:1;l=w?b:a;printf("%s %i\n",v[w+1],l);}

Example output:

N:\>golf.exe everything works
everything 10