There are some basic things you can do to speed up your sweepstakes entry that will not cost you anything. The first that is often ignored is Clear Your Internet Temporary Files. Every time your web browser loads a web page it has to search your temporary files for a match. If you are using a slower/older system this can be slow. Clear your temporary files regularly to speed your sweepstakes entry up.
Another tip would be to limit the amount of add-on tools bars that you have installed in your web browser. I only use 2 add-on tools, Google and Roboform. Most toolbars will periodically download information from the internet. If you have many installed you'll have a very needlessly chatty system.
Many sweepstakes forms today use some form of active content. Most of the active content either requires javascript ( on by default in most web browsers ) or Flash. Adobe flash can be downloaded and installed for free from their website. Some sweepstakes forms cannot even be viewed without flash.
Last but not least, please don't try and enter sweepstakes with WebTV or some other web box. These systems were meant for reading articles and email online and not much else. We receive feedback from people on a regular basis that can't enter certain sweepstakes and most often it's due to using WebTV. A lean mean computer will enter more sweepstakes and hopefully bring you more prizes!
Hope for the best