Tough choice. The radio serie, I would have to say, just because of it's medium although it's far from perfect and misses out lots of good gags that got added later. Hearing the new adaptions was wonderful.
You can get scripts - see series 1 and 2 (http://www.amazon.co.uk/exec/obidos/ASIN/0330419579/qid=1124104928/sr=8-1/ref=sr_8_xs_ap_i1_xgl/026-2982547-3299640) and the new series 3 to 5 (http://www.amazon.co.uk/exec/obidos/ASIN/0330435108/ref=pd_nfy_fr_gw_nr_1/026-2982547-3299640).
no subject
You can get scripts - see series 1 and 2 (http://www.amazon.co.uk/exec/obidos/ASIN/0330419579/qid=1124104928/sr=8-1/ref=sr_8_xs_ap_i1_xgl/026-2982547-3299640) and the new series 3 to 5 (http://www.amazon.co.uk/exec/obidos/ASIN/0330435108/ref=pd_nfy_fr_gw_nr_1/026-2982547-3299640).