If you only have a couple items, you can probably take them to customer service to have them ring you up at many stores. In Sam's Club last night, we only had two things so we took them to the guy at the snack bar to ring them up.
i don't think self-checkouts are always that much quicker unless no one is in front of you. I find that people who check themselves out are much slower than the cashiers. I like to self-check out only because I can see each price as it is rung up. Usually I'm too busy packing to notice the prices when a cashier does it.
I also look for the "regular" cashiers. They are usually the quickest.
I agree the people who use self check generally are slower. I think some think it is faster because they are in control of the situation rather than waiting for someone else to do it. I use it occassionally but I know I am quick from when I used to be a cashier there myself. However, using checks or gift cards are generally a hassle as are some items like produce you have to weigh.
I go in the lines with the fewest people, regardless of how much stuff they have. Processing payment is the same no matter what (unless you have coupons of course), so standing in line behind the person with the cart full of groceries is usually quicker than the "quick lines" behind 4 people with 10 items each.
ETA: I also don't like when people go to random departments to check out, unless of course you have business in that department. For example, if I'm buying ammo at WalMart and have 4 other items, then it's ok to check out at sporting goods, because I have to pay for my ammo there anyway. Bringing groceries to sporting goods because I'm too impatient to go to the normal lanes isn't right imo because the reps are there to assist that department, versus checkout people whose job it is to be in the checkout registers.
I prefer the self-check out and really hate some stores that limit the number of items you can scan on those lanes.
The old wives' tale is to look for a male cashier. Supposedly a male cashier is actually a management trainee so they are going to be more professional and knowledgeable.
I personally look for a cashier who is busy and not talking to other cashiers or employees. Some cashiers get so into their conversation with their co-workers, they don't stop when they have a customer. It is almost like the customer is an interruption to their day.
Other than that, my recommendation is to time when you shop. It might be a regional thing but I quickly learned not to go to the store in the hour after school lets out. OMG, there are so many moms and kids, it is nearly impossible to find anything much less check out.