I have an classic Multibit wallet, but I don't remember the password. I do have 12 words that I wrote down. Is there any way I can open my wallet?
Classic multibit didn't give out 12 words. Multibit hd did though. do you have multibit hd or classic multibit? If you have multibit HD you can restore your wallet in electrum as per this guide.
If you have multibit classic then you need to export the wallet's private keys which requires that you have the password. Since you don't have that you can attempt to brute force it using this script.
You are all right so I'm going to do my best helping you with stop simple steps taken from various sites. Download the html tool from this site: https://github.com/iancoleman/bip39 Its not a crime to be extra carefull with such things so On your offline machine access/open/load the 'bip39-standalone.html' file you downloaded from github.
Enter your MultiBit recovery phrase/seed in the webpage next to 'BIP39 Mnemonic'
Choose number of words = '12' (or set the number of words for how many were in your recovery phrase)
Leave all the rest of the entries set to their default
Scroll down to the 'Derived Addresses' section and you should now see a list of addresses that will match the list of addresses in Multibit for your wallet.
Find the address in question and copy its private key.
From here you should open an account in any choosen wallet and import the private key into that wallet - I offer you a good wallet I always used and it is blockchain.info - which is a nice and secure wallet - but that's only my opinion!