That's a hard one. Both are in my top 10 all time games, but I guess I'll go with FF8 just because of the sheer amount of content in the game compared to Chrono Cross. Both are absolute masterpieces in my book.

I personally love the Dreamcast, but I guess PS2 wins because of the sheer number of titles.

I would probably start with the REmake for the Gamecube. You also can't go wrong with the original for the PS1.

Forgot to mention that I finally found Robo Army after years of searching:

Robo Army Neo Geo CD- $45.00 (w/out spine card)

I went a little crazy and picked up a lot of stuff of of Ebay. Shipping is included:

Japanese Neo Geo AES w/ Fatal Fury Special (complete)- $260.00

King of Fighters 95 AES complete (Japanese)

Samurai Spirits AES- $20.00 (game only)

King of Fighters 98 Neo Geo CD (w/out spine card)- $15.00

World Heroes Perfect Neo Geo CD (w/out spine card)- 15.00

I also grabbed a few Dreamcast games at a local game shop:

Phantasy Star Online, Hydro Thunder, and Daytona USA- $5.00 each (all complete)