- do I need to patch the game to any particular version prior to doing that?
AFAIK it's included, but to be sure it's better to install the unofficial patch first.
- will the resolution and monitor aspect (16:9) be fixed with STA installed or does it require a separate fix?
STA has a separate fix for widescreen monitors, or use the fix from the sticky FAQ. Regarding the cut first line see "Q. The upper part of the message is not visible on the monitor. How to fix it?" in the FAQ.
- is Steel Panzer Mod 2.0 better than STA?
SPM is no longer updated, so STA is better I guess. But SPM is more stable in my opinion.
Also, I want to try the STA but the files seem to be only available through 4shared. That file hosting site wants me to either use my Facebook account to log in or register me as a user.. I really don'y feel like doing that so.. is there any other way to get STA?
I don't think so, but you could try looking for a link generator for 4shared or using a login from services like bugmenot.