Is this usable with.....

This is going to sound strange, but AD&D 1.0/2.0? They're the only source books I have, specifically, the World of Greyhawk. I'm only 23, but I've been DMing Greyhawk campaigns since I was about 15. I haven't DMed in a good long while, and I was getting ready to DM a campaign for some friends over Skype when I found this site. So I'd like to know if this is compatible with the rulesets I plan on using. If this is a stupid question, feel free to let me know. I'm VERY new to this roll20 thing.

Roll20 is system agnostic. You can play pretty much any game that you could play at a regular table with dice, mini's etc. You shouldn't have any difficulties in playing AD&D with it.

Ah, alright. Thank you.