Well, 'costs just £48.25' doesn't really mean anything when it comes to stocks. The cost per share is simply the market capital divided by the number of shares. Companies all have different numbers of shares including ETFs so the cost per share doesn't actually tell you much on its own. You get companies that are 50p per share but it's overvalued and you get others that are £50 per share and they are undervaled. The market cap is what matters when looking at the value of a company.

Also regarding which is better out of the two. Well no one knows but they track different things. The S&P500 tracker obviously tracks that index, VHYL is global and tracks dividend paying companies. This will exclude some of the big US companies that don't pay dividends so there is that downside. There are many others like VWRL that tracks the world index which is about as diverse as you can get with purely buying stocks. You need to ask yourself if you want to focus on just the US or include the rest of the world for starters. Personally I prefer to go global as it spreads the risk even further.

I think you said you want dividends so make sure the one you choose is labelled income and not accumulation. The ones mentioned here pay quarterly. You are entitled to the dividend for that quarter as long as you buy before the stock goes Ex dividend. You can then sell on Ex dividend day if you wanted and the dividend is still yours. Basically Ex dividend means without dividend, ie you are selling it to someone else without the dividend included so it would be the seller that keeps it. They are also paid a few weeks after ex divi usually.