Actually, the lower of the two side ads does display Google ads and those are usually a lot more relevant than the UGO one above as they're targetted with adsense. However, as far as I'm aware the Google ads continually generate less revenue than the UGO ads -- go figure.
Yes, few of us will deny that having the sexually themed ads is a little distasteful, but unfortunately every time we've asked UGO for them to be removed they've ended up reappearing some time later. Perhaps another chat is needed with UGO, and this thread will probably motivate those who deal with it to do so. Your feedback isn't just ignored, contrary to what Ray Jones thinks.
As for blocking ads, please don't discuss that here. While everybody's free to do it, the fact is that running LucasForums (and the LFNetwork) takes multiple dedicated servers, huge volumes of bandwidth, and hundreds upon hundreds of dollars. Without ad revenue the network simply couldn't be sustained, so unfortunately we can't really condone blocking the ads.