There's a big over 35 group--40% SRD fans 40% George Martin fans and 20% Walter Jon Williams (and others) fans--if you avoid the gamers and the SW/ST nerds you'll be ok...
I'll have to check the Bubonicon archives, I think SRD once was The Guest of Honor but it was a long time ago...they've had some really good ones...
Edit: just checked and NO Stephen R. Donaldson has NEVER been the Guest of Honor, here's the roll:
B36 (2004) Connie Willis
B35 (2003) *Charles de Lint
B34 (2002) • Esther Friesner
B33 (2001) • Sarah Ziettel
B32 (2000) • Walter Jon Williams
B31 (1999) • Jack McDevitt
B30 (1998) • Robert J. Sawyer, Jane Lindskold
B29 (1997) • John Barnes
B28 (1996) • Dennis McKiernan
B27 (1995) • Harry Turtledove
B26 (1994) • Michael Stackpole
B25 (1993) • Kevin J. Anderson, Robert C. Cornett
B24 (1992) • Thorarinn Gunnarsson
B23 (1991) • Simon Hawke
B22 (1990) • Jennifer Roberson
B21 (1989) • Melinda Snodgrass
B20 (1988) • John E. Stith
B19 (1987) • Parke Godwin
B18 (1986) • George R. R. Martin
B17 (1985) • Fred Saberhagen
B16 (1984) • Spider & Jeanne Robinson
B15 (1983) • Jack Williamson
B14 (1982) • Chelsea Quinn Yarbro
B13 (1981) • Roger Zelazny
B12 (1980) • C.J. Cherryh
B11 (1979) • Orson Scott Card
B10 (1978) • Gordon R. Dickson
B9 (1977) • Gordon Eklund
B8 (1976) • Bill Rotsler
B7 (1975) • Ed Bryant
B6 (1974) • F.M. Busby
B5 (1973) • Robert Silverberg
B4 (1972) • Ted White
B3 (1971) • Jack Williamson